'test -e' is not supported on Solaris, replace with '-f' or '-d'.

diff --git a/configure b/configure
index ec7c412..ed725bb 100755
--- a/configure
+++ b/configure
@@ -3861,7 +3861,7 @@
  
         if test $OPENGL = "yes" -o $OPENGL = "normal"
     then
-        if test -e /usr/X11R6/lib/libGL.a -a ! -e /usr/X11R6/lib/libGL.so
+        if test -f /usr/X11R6/lib/libGL.a -a ! -f /usr/X11R6/lib/libGL.so
         then
 	    { echo "configure: error: /usr/X11R6/lib/libGL.a is present on your system.
 This prevents linking to OpenGL. Delete the file and restart configure." 1>&2; exit 1; }