--- ./programs/Xserver/os/save_xprintf.c	2005-11-23 07:32:18.000000000 +0000
+++ ./programs/Xserver/os/xprintf.c	2005-11-23 07:31:55.000000000 +0000
@@ -48,12 +48,22 @@
 {
     char *ret;
     int size;
-    va_list va2;
-
-    va_copy(va2, va);
-    size = vsnprintf(NULL, 0, format, va2);
-    va_end(va2);
-
+    char *t=NULL;
+    int buffSize=1; /* larger default value is harder to test, 
+                       but faster */
+    for (;;)
+      {
+    t=(char *)Xalloc(buffSize);
+    if (t==NULL)
+      return NULL;
+    size = vsnprintf(t, buffSize, format, va);
+    xfree(t);
+    /* be afraid, we can not trust the return value from vsnprintf
+       unless it is shorter than the allocated buffer */
+    if ((size>0)&&(size<buffSize))
+      break;
+    buffSize*=2;
+      }
     ret = (char *)Xalloc(size + 1);
     if (ret == NULL)
         return NULL;