diff --git a/src/dummy_cursor.c b/src/dummy_cursor.c
index aa6021f..07a89bf 100644
--- a/src/dummy_cursor.c
+++ b/src/dummy_cursor.c
@@ -62,7 +62,7 @@ dummyLoadCursorImage(ScrnInfoPtr pScrn, unsigned char *src)
 static Bool
 dummyUseHWCursor(ScreenPtr pScr, CursorPtr pCurs)
 {
-    DUMMYPtr dPtr = DUMMYPTR(xf86Screens[pScr->myNum]);
+    DUMMYPtr dPtr = DUMMYPTR(xf86ScreenToScrn(pScr));
     return(!dPtr->swCursor);
 }
 
@@ -77,7 +77,7 @@ dummyRealizeCursor(xf86CursorInfoPtr infoPtr, CursorPtr pCurs)
 Bool
 DUMMYCursorInit(ScreenPtr pScreen)
 {
-    DUMMYPtr dPtr = DUMMYPTR(xf86Screens[pScreen->myNum]);
+    DUMMYPtr dPtr = DUMMYPTR(xf86ScreenToScrn(pScreen));
 
     xf86CursorInfoPtr infoPtr;
     infoPtr = xf86CreateCursorInfoRec();
diff --git a/src/dummy_dga.c b/src/dummy_dga.c
index 9710aef..a35f3c9 100644
--- a/src/dummy_dga.c
+++ b/src/dummy_dga.c
@@ -33,7 +33,7 @@ DGAFunctionRec DUMMYDGAFuncs = {
 Bool
 DUMMYDGAInit(ScreenPtr pScreen)
 {   
-   ScrnInfoPtr pScrn = xf86Screens[pScreen->myNum];
+   ScrnInfoPtr pScrn = xf86ScreenToScrn(pScreen);
    DUMMYPtr pDUMMY = DUMMYPTR(pScrn);
    DGAModePtr modes = NULL, newmodes = NULL, currentMode;
    DisplayModePtr pMode, firstMode;
diff --git a/src/dummy_driver.c b/src/dummy_driver.c
index 791855f..f5d1f4c 100644
--- a/src/dummy_driver.c
+++ b/src/dummy_driver.c
@@ -532,7 +532,7 @@ DUMMYScreenInit(int scrnIndex, ScreenPtr pScreen, int argc, char **argv)
      * we need to get the ScrnInfoRec for this screen, so let's allocate
      * one first thing
      */
-    pScrn = xf86Screens[pScreen->myNum];
+    pScrn = xf86ScreenToScrn(pScreen);
     dPtr = DUMMYPTR(pScrn);
     DUMMYScrn = pScrn;
 
@@ -734,7 +734,7 @@ DUMMYSaveScreen(ScreenPtr pScreen, int mode)
     DUMMYPtr dPtr;
 
     if (pScreen != NULL) {
-	pScrn = xf86Screens[pScreen->myNum];
+	pScrn = xf86ScreenToScrn(pScreen);
 	dPtr = DUMMYPTR(pScrn);
 
 	dPtr->screenSaver = xf86IsUnblank(mode);