diff --git a/collects/mred/mred-sig.ss b/collects/mred/mred-sig.ss
index 5498a605..daeb6129 100644
--- a/collects/mred/mred-sig.ss
+++ b/collects/mred/mred-sig.ss
@@ -99,6 +99,7 @@
      get-top-level-focus-window
      get-top-level-windows
      get-window-text-extent
+     gl-config%
      gl-context<%>
      graphical-read-eval-print-loop
      group-box-panel%
diff --git a/collects/mred/mred.ss b/collects/mred/mred.ss
index e2d40a89..5a84fc72 100644
--- a/collects/mred/mred.ss
+++ b/collects/mred/mred.ss
@@ -1790,7 +1790,7 @@
 	   (stretchable-in-y (not horizontal?))))))))
 
 (define wx-canvas% (make-canvas-glue%
-		    (class100 (make-control% wx:canvas% 0 0 #t #t) (parent x y w h style)
+		    (class100 (make-control% wx:canvas% 0 0 #t #t) (parent x y w h style gl-config)
 		      (private-field
 			[tabable? #f])
 		      (public
@@ -1803,7 +1803,7 @@
 			 (lambda (code alpha? meta?)
 			   (or meta? (not tabable?)))])
 		      (sequence
-			(super-init style parent x y w h style)))))
+			(super-init style parent x y w h style "canvas" gl-config)))))
 
 ;--------------------- tab group -------------------------
 
@@ -5007,7 +5007,7 @@
 
 (define canvas%
   (class100*/kw basic-canvas% ()
-		[(parent [style null] [paint-callback default-paint-cb] [label #f])
+		[(parent [style null] [paint-callback default-paint-cb] [label #f] [gl-config #f])
 		 canvas%-keywords]
     (private-field [paint-cb paint-callback]
 		   [has-x? (memq 'hscroll style)]
@@ -5118,7 +5118,8 @@
 					    (mred->wx-container parent)
 					    -1 -1 
 					    (+ ds (if (memq 'combo style) side-combo-width 0)) ds
-					    style)))
+					    style
+					    gl-config)))
 		    wx)
 		  (lambda ()
 		    (let ([cwho '(constructor canvas)])
@@ -8140,7 +8141,8 @@
 	   eventspace-shutdown?
 	   get-panel-background
 	   send-event
-	   gl-context<%>)
+	   gl-context<%>
+	   gl-config%)
 
 (define the-color-database (wx:get-the-color-database))
 (define the-font-name-directory (wx:get-the-font-name-directory))
diff --git a/collects/mred/private/kernel.ss b/collects/mred/private/kernel.ss
index 85c54280..5b02ea3f 100644
--- a/collects/mred/private/kernel.ss
+++ b/collects/mred/private/kernel.ss
@@ -297,6 +297,8 @@
   (define-function set-editor-print-margin)
   (define-function get-editor-print-margin)
   (define-class bitmap% object% #f
+    get-gl-config
+    set-gl-config
     set-loaded-mask
     get-loaded-mask
     save-file
@@ -428,6 +430,33 @@
     call-as-current
     swap-buffers
     ok?)
+  (define-class gl-config% object% #f
+    sizeof-bitfield
+    sizeof-enum
+    sizeof-clampd
+    sizeof-clampf
+    sizeof-sizei
+    sizeof-boolean
+    sizeof-double
+    sizeof-float
+    sizeof-uint
+    sizeof-int
+    sizeof-ushort
+    sizeof-short
+    sizeof-ubyte
+    sizeof-byte
+    get-double-buffered
+    set-double-buffered
+    get-stereo
+    set-stereo
+    get-stencil-size
+    set-stencil-size
+    get-accum-size
+    set-accum-size
+    get-depth-size
+    set-depth-size
+    get-multisample-size
+    set-multisample-size)
   (define-class event% object% ([time-stamp 0])
     get-time-stamp
     set-time-stamp)