Fixed a paint problem reported by Mike McCormack.

diff --git a/controls/edit.c b/controls/edit.c
index ddd7dcb..5920bf4 100644
--- a/controls/edit.c
+++ b/controls/edit.c
@@ -3083,7 +3083,7 @@
 
 		hrgn = CreateRectRgn(0, 0, 0, 0);
 		EDIT_BuildLineDefs_ML(wnd, es, s, s + strl, 
-				strl - (es->selection_end - es->selection_start), hrgn);
+				strl - abs(es->selection_end - es->selection_start), hrgn);
 	}
 	else
 	    EDIT_CalcLineWidth_SL(wnd, es);