diff --git a/src/ParagraphMetrics.cpp b/src/ParagraphMetrics.cpp
index 801642e525..1e4410644c 100644
--- a/src/ParagraphMetrics.cpp
+++ b/src/ParagraphMetrics.cpp
@@ -103,9 +103,10 @@ size_t ParagraphMetrics::computeRowSignature(Row const & row,
 	}
 
 	Dimension const & d = row.dimension();
-	char_type const b[] = { row.sel_beg, row.sel_end, d.wid, d.asc, d.des};
-	// Each of the variable to process is 4 bytes: 4x5 = 20
-	crc.process_bytes(b, 20);
+	char_type const b[] = { row.sel_beg, row.sel_end, 
+		row.left_margin_sel, row.right_margin_sel, d.wid, d.asc, d.des};
+	// Each of the variable to process is 4 bytes: 4x7 = 28
+	crc.process_bytes(b, 28);
 
 	return crc.checksum();
 }
diff --git a/src/Row.cpp b/src/Row.cpp
index 975940310c..8c8383b24f 100644
--- a/src/Row.cpp
+++ b/src/Row.cpp
@@ -18,6 +18,8 @@
 
 #include "Row.h"
 
+#include "DocIterator.h"
+
 #include "support/debug.h"
 
 
@@ -26,13 +28,15 @@ namespace lyx {
 
 Row::Row()
 	: separator(0), label_hfill(0), x(0),
-	sel_beg(-1), sel_end(-1), changed_(false), crc_(0), pos_(0), end_(0)
+	sel_beg(-1), sel_end(-1), changed_(false), crc_(0), 
+	pos_(0), end_(0), left_margin_sel(false), right_margin_sel(false)
 {}
 
 
 Row::Row(pos_type pos)
 	: separator(0), label_hfill(0), x(0),
-	sel_beg(-1), sel_end(-1), changed_(false), crc_(0), pos_(pos), end_(0)
+	sel_beg(-1), sel_end(-1), changed_(false), crc_(0), 
+	pos_(0), end_(0), left_margin_sel(false), right_margin_sel(false)
 {}
 
 
@@ -61,6 +65,46 @@ void Row::endpos(pos_type p)
 }
 
 
+bool Row::isMarginSelected(bool margin_begin, DocIterator const & beg, 
+								 DocIterator const & end) const
+{
+	pos_type const sel_pos = margin_begin ? sel_beg : sel_end;
+	pos_type const margin_pos = margin_begin ? pos_ : end_;
+
+	// Is the chosen margin selected ?
+	if (sel_pos == margin_pos) {
+		if (beg.pos() == end.pos())
+			// This is a special case in which the space between after 
+			// pos i-1 and before pos i is selected, i.e. the margins
+			// (see DocIterator::boundary_).
+			return beg.boundary() && !end.boundary();
+		else if (end.pos() == margin_pos)
+			// If the selection ends around the margin, it is only
+			// drawn if the cursor is after the margin.
+			return !end.boundary();
+		else if (beg.pos() == margin_pos)
+			// If the selection begins around the margin, it is 
+			// only drawn if the cursor is before the margin.
+			return beg.boundary();
+		else 
+			return true;
+	}
+	return false;
+}
+
+
+void Row::setSelectionAndMargins(DocIterator const & beg, 
+								 DocIterator const & end) const
+{
+	setSelection(beg.pos(), end.pos());
+	
+	if (selection()) {
+		right_margin_sel = isMarginSelected(false, beg, end);
+		left_margin_sel = isMarginSelected(true, beg, end);
+	}
+}
+
+
 void Row::setSelection(pos_type beg, pos_type end) const
 {
 	if (pos_ >= beg && pos_ <= end)
@@ -79,6 +123,12 @@ void Row::setSelection(pos_type beg, pos_type end) const
 }
 
 
+bool Row::selection() const
+{
+	return sel_beg != -1 && sel_end != -1;
+}
+
+
 void Row::dump(char const * s) const
 {
 	LYXERR0(s << " pos: " << pos_ << " end: " << end_
diff --git a/src/Row.h b/src/Row.h
index a3afad4c11..055608bc2e 100644
--- a/src/Row.h
+++ b/src/Row.h
@@ -22,6 +22,8 @@
 
 namespace lyx {
 
+class DocIterator;
+
 /**
  * An on-screen row of text. A paragraph is broken into a
  * RowList for display. Each Row contains position pointers
@@ -45,7 +47,13 @@ public:
 	  * time.
 	  */
 	void setSelection(pos_type sel_beg, pos_type sel_end) const;
-
+	///
+	bool selection() const;
+	/// Set the selection begin and end and whether the margin begin and end
+	/// are selected.
+	void setSelectionAndMargins(DocIterator const & beg, 
+		DocIterator const & end) const;
+	
 	///
 	void pos(pos_type p);
 	///
@@ -80,7 +88,21 @@ public:
 	mutable pos_type sel_beg;
 	///
 	mutable pos_type sel_end;
+	///
+	mutable bool left_margin_sel;
+	///
+	mutable bool right_margin_sel;
+
 private:
+	/// Decides whether the margin is selected.
+	/**
+	  * \param margin_begin
+	  * \param beg
+	  * \param end
+	  */
+	bool isMarginSelected(bool margin_begin, DocIterator const & beg, 
+		DocIterator const & end) const;
+
 	/// has the Row appearance changed since last drawing?
 	mutable bool changed_;
 	/// CRC of row contents.
diff --git a/src/TextMetrics.cpp b/src/TextMetrics.cpp
index 84d268afb4..cc25afb755 100644
--- a/src/TextMetrics.cpp
+++ b/src/TextMetrics.cpp
@@ -1986,15 +1986,19 @@ void TextMetrics::drawParagraph(PainterInfo & pi, pit_type pit, int x, int y) co
 		&& cur.anchor().text() == text_
 		&& pit >= sel_beg.pit() && pit <= sel_end.pit();
 
+	// We store the begin and end pos of the selection relative to this par
+	DocIterator sel_beg_par = cur.selectionBegin();
+	DocIterator sel_end_par = cur.selectionEnd();
+	
 	// We care only about visible selection.
 	if (selection) {
 		if (pit != sel_beg.pit()) {
-			sel_beg.pit() = pit;
-			sel_beg.pos() = 0;
+			sel_beg_par.pit() = pit;
+			sel_beg_par.pos() = 0;
 		}
 		if (pit != sel_end.pit()) {
-			sel_end.pit() = pit;
-			sel_end.pos() = sel_end.lastpos();
+			sel_end_par.pit() = pit;
+			sel_end_par.pos() = sel_end_par.lastpos();
 		}
 	}
 
@@ -2011,9 +2015,18 @@ void TextMetrics::drawParagraph(PainterInfo & pi, pit_type pit, int x, int y) co
 		RowPainter rp(pi, *text_, pit, row, bidi, x, y);
 
 		if (selection)
-			row.setSelection(sel_beg.pos(), sel_end.pos());
+			row.setSelectionAndMargins(sel_beg_par, sel_end_par);
 		else
 			row.setSelection(-1, -1);
+		
+		// The row knows nothing about the paragraph, so we have to check
+		// whether this row is the first or last and update the margins.
+		if (row.selection()) {
+			if (row.sel_beg == 0)
+				row.left_margin_sel = sel_beg.pit() < pit;
+			if (row.sel_end == sel_end_par.lastpos())
+				row.right_margin_sel = sel_end.pit() > pit;
+		}
 
 		// Row signature; has row changed since last paint?
 		row.setCrc(pm.computeRowSignature(row, bparams));
@@ -2035,34 +2048,18 @@ void TextMetrics::drawParagraph(PainterInfo & pi, pit_type pit, int x, int y) co
 			pi.pain.fillRectangle(x, y - row.ascent(),
 				width(), row.height(), pi.background_color);
 		}
-
-		bool row_selection = row.sel_beg != -1 && row.sel_end != -1;
-		if (row_selection) {
-			DocIterator beg = bv_->cursor().selectionBegin();
-			DocIterator end = bv_->cursor().selectionEnd();
-			// FIXME (not here): pit is not updated when extending
-			// a selection to a new row with cursor right/left
-			bool const beg_margin = beg.pit() < pit;
-			bool const end_margin = end.pit() > pit;
-			beg.pit() = pit;
-			beg.pos() = row.sel_beg;
-			end.pit() = pit;
-			end.pos() = row.sel_end;
-			if (end.pos() == row.endpos()) {
-				// selection goes till the end of the row.
-				end.boundary(true);
-			}
-			drawRowSelection(pi, x, row, beg, end, beg_margin, end_margin);
-		}
+		
+		if (row.selection())
+			drawRowSelection(pi, x, row, cur, pit);
 
 		// Instrumentation for testing row cache (see also
 		// 12 lines lower):
 		if (lyxerr.debugging(Debug::PAINTING) && inside
-			&& (row_selection || pi.full_repaint || row_has_changed)) {
+			&& (row.selection() || pi.full_repaint || row_has_changed)) {
 				string const foreword = text_->isMainText(bv_->buffer()) ?
 					"main text redraw " : "inset text redraw: ";
 			LYXERR(Debug::PAINTING, foreword << "pit=" << pit << " row=" << i
-				<< " row_selection="	<< row_selection
+				<< " row_selection="	<< row.selection()
 				<< " full_repaint="	<< pi.full_repaint
 				<< " row_has_changed="	<< row_has_changed);
 		}
@@ -2091,28 +2088,39 @@ void TextMetrics::drawParagraph(PainterInfo & pi, pit_type pit, int x, int y) co
 
 
 void TextMetrics::drawRowSelection(PainterInfo & pi, int x, Row const & row,
-		DocIterator const & beg, DocIterator const & end,
-		bool drawOnBegMargin, bool drawOnEndMargin) const
+		Cursor const & curs, pit_type pit) const
 {
+	DocIterator beg = curs.selectionBegin();
+	beg.pit() = pit;
+	beg.pos() = row.sel_beg;
+
+	DocIterator end = curs.selectionEnd();
+	end.pit() = pit;
+	end.pos() = row.sel_end;
+
+	bool const begin_boundary = beg.pos() >= row.endpos();
+	bool const end_boundary = row.sel_end == row.endpos();
+
 	Buffer & buffer = bv_->buffer();
 	DocIterator cur = beg;
-	int x1 = cursorX(beg.top(), beg.boundary());
-	int x2 = cursorX(end.top(), end.boundary());
+	cur.boundary(begin_boundary);
+	int x1 = cursorX(beg.top(), begin_boundary);
+	int x2 = cursorX(end.top(), end_boundary);
 	int y1 = bv_->getPos(cur, cur.boundary()).y_ - row.ascent();
 	int y2 = y1 + row.height();
 
 	// draw the margins
-	if (drawOnBegMargin) {
+	if (row.left_margin_sel) {
 		if (text_->isRTL(buffer, beg.paragraph())) {
-			int lm = bv_->leftMargin();
-			pi.pain.fillRectangle(x + x1, y1, width() - lm - x1, y2 - y1, Color_selection);
+			int const w = width() - bv_->leftMargin() - x1;
+			pi.pain.fillRectangle(x + x1, y1, w, y2 - y1, Color_selection);
 		} else {
-			int rm = bv_->rightMargin();
+			int const rm = bv_->rightMargin();
 			pi.pain.fillRectangle(rm, y1, x1 - rm, y2 - y1, Color_selection);
 		}
 	}
 
-	if (drawOnEndMargin) {
+	if (row.right_margin_sel) {
 		if (text_->isRTL(buffer, beg.paragraph())) {
 			int rm = bv_->rightMargin();
 			pi.pain.fillRectangle(x + rm, y1, x2 - rm, y2 - y1, Color_selection);
diff --git a/src/TextMetrics.h b/src/TextMetrics.h
index 1a0945d4ff..78825c3985 100644
--- a/src/TextMetrics.h
+++ b/src/TextMetrics.h
@@ -160,8 +160,7 @@ private:
 
 	/// draw selection for a single row
 	void drawRowSelection(PainterInfo & pi, int x, Row const & row,
-		DocIterator const & beg, DocIterator const & end, 
-		bool drawOnBegMargin, bool drawOnEndMargin) const;
+		Cursor const & cur, pit_type const pit) const;
 
 // Temporary public:
 public: