diff --git a/src/add-ons/kernel/drivers/graphics/matrox/UPDATE.html b/src/add-ons/kernel/drivers/graphics/matrox/UPDATE.html
index 5ab6edb43b..77661e26c0 100644
--- a/src/add-ons/kernel/drivers/graphics/matrox/UPDATE.html
+++ b/src/add-ons/kernel/drivers/graphics/matrox/UPDATE.html
@@ -4,6 +4,18 @@
 </head>
 <body>
 <p><h2>Changes done for each driverversion:</h2></p>
+<p><h1>head (svn 0.27, Rudolf)</h1></p>
+<ul>
+<li><strong>G200-G550:</strong>
+<ul>
+<li>The overlay engine code now respects the B_OVERLAY_COLOR_KEY flag instead of forcing keying ON.
+</ul>
+<li><strong>General:</strong>
+<ul>
+<li>Hook GET_ACCELERANT_DEVICE_INFO now returns more detailed info about the card in use;
+<li>Hooks INIT_ACCELERANT and CLONE_ACCELERANT now enforce their correct use; returning error B_NOT_ALLOWED in case of errors.
+</ul>
+</ul>
 <p><h1>mga_driver 0.26 (Rudolf)</h1></p>
 <ul>
 <li><strong>G200-G550:</strong>
diff --git a/src/add-ons/kernel/drivers/graphics/matrox/driver.c b/src/add-ons/kernel/drivers/graphics/matrox/driver.c
index 4206c4914a..6b4f65722b 100644
--- a/src/add-ons/kernel/drivers/graphics/matrox/driver.c
+++ b/src/add-ons/kernel/drivers/graphics/matrox/driver.c
@@ -4,7 +4,7 @@
 
 	Other authors:
 	Mark Watson;
-	Rudolf Cornelissen 3/2002-11/2005.
+	Rudolf Cornelissen 3/2002-1/2006.
 */
 
 /* standard kernel driver stuff */
@@ -791,6 +791,9 @@ static status_t open_hook (const char* name, uint32 flags, void** cookie) {
 	si->device = di->pcii.device;
 	si->function = di->pcii.function;
 
+	/* ensure that the accelerant's INIT_ACCELERANT function can be executed */
+	si->accelerant_in_use = false;
+
 	/* map the device */
 	result = map_device(di);
 	if (result < 0) goto free_shared;
