diff --git a/mozilla/gfx/thebes/src/gfxBeOSPlatform.cpp b/mozilla/gfx/thebes/src/gfxBeOSPlatform.cpp
index 62ff302800a..f9cb5f8ea0b 100644
--- a/mozilla/gfx/thebes/src/gfxBeOSPlatform.cpp
+++ b/mozilla/gfx/thebes/src/gfxBeOSPlatform.cpp
@@ -395,7 +395,7 @@ gfxBeOSPlatform::IsExistingFont(const nsACString &aFontName)
         goto end;
 
     result = fs->nfont;
-    NS_ASSERTION(result == 1, "What's this case?");
+    NS_ASSERTION(result == 0 || result == 1, "What's this case?");
 
     if (result > 0)
         mAliasForSingleFont.AppendCString(aFontName);
diff --git a/mozilla/gfx/thebes/src/gfxPlatformGtk.cpp b/mozilla/gfx/thebes/src/gfxPlatformGtk.cpp
index 2b404c97d36..174729ef113 100644
--- a/mozilla/gfx/thebes/src/gfxPlatformGtk.cpp
+++ b/mozilla/gfx/thebes/src/gfxPlatformGtk.cpp
@@ -555,7 +555,7 @@ gfxPlatformGtk::IsExistingFont(const nsACString &aFontName)
         goto end;
 
     result = fs->nfont;
-    NS_ASSERTION(result == 1, "What's this case?");
+    NS_ASSERTION(result == 0 || result == 1, "What's this case?");
 
     if (result > 0)
         mAliasForSingleFont.AppendCString(aFontName);