--- a/gfx/thebes/src/gfxAtsuiFonts.cpp
+++ b/gfx/thebes/src/gfxAtsuiFonts.cpp
@@ -90,17 +90,18 @@ OSStatus ATSClearGlyphVector(void *glyph
 #endif
 
 eFontPrefLang GetFontPrefLangFor(PRUint8 aUnicodeRange);
 
 gfxAtsuiFont::gfxAtsuiFont(MacOSFontEntry *aFontEntry,
                            const gfxFontStyle *fontStyle, PRBool aNeedsBold)
     : gfxFont(aFontEntry, fontStyle),
       mFontStyle(fontStyle), mATSUStyle(nsnull),
-      mHasMirroring(PR_FALSE), mHasMirroringLookedUp(PR_FALSE), mAdjustedSize(0.0f)
+      mHasMirroring(PR_FALSE), mHasMirroringLookedUp(PR_FALSE),
+      mFontFace(nsnull), mScaledFont(nsnull), mAdjustedSize(0.0f)
 {
     ATSUFontID fontID = aFontEntry->GetFontID();
     ATSFontRef fontRef = FMGetATSFontRefFromFont(fontID);
 
     // determine whether synthetic bolding is needed
     PRInt8 baseWeight, weightDistance;
     mFontStyle->ComputeWeightAndOffset(&baseWeight, &weightDistance);
     PRUint16 targetWeight = (baseWeight * 100) + (weightDistance * 100);
@@ -111,16 +112,19 @@ gfxAtsuiFont::gfxAtsuiFont(MacOSFontEntr
     // at the first bolder step beyond available faces, no matter how light the boldest face
     if (!aFontEntry->IsBold()
         && ((weightDistance == 0 && targetWeight >= 600) || (weightDistance > 0 && aNeedsBold))) 
     {
         mSyntheticBoldOffset = 1;  // devunit offset when double-striking text to fake boldness   
     }
 
     InitMetrics(fontID, fontRef);
+    if (!mIsValid) {
+        return;
+    }
 
     mFontFace = cairo_quartz_font_face_create_for_atsu_font_id(fontID);
 
     cairo_matrix_t sizeMatrix, ctm;
     cairo_matrix_init_identity(&ctm);
     cairo_matrix_init_scale(&sizeMatrix, mAdjustedSize, mAdjustedSize);
 
     // synthetic oblique by skewing via the font matrix
@@ -261,18 +265,31 @@ gfxAtsuiFont::InitMetrics(ATSUFontID aFo
     // we don't know where the line-breaks are at the time we're applying shaping,
     // and it would be bad to put words with line-end swashes into the text-run
     // cache until we have a way to distinguish them from mid-line occurrences.
     DisableUncommonLigaturesAndLineBoundarySwashes(mATSUStyle);
 
     /* Now pull out the metrics */
 
     ATSFontMetrics atsMetrics;
-    ATSFontGetHorizontalMetrics(aFontRef, kATSOptionFlagsDefault,
+    OSStatus err;
+    
+    err = ATSFontGetHorizontalMetrics(aFontRef, kATSOptionFlagsDefault,
                                 &atsMetrics);
+                                
+    if (err != noErr) {
+        mIsValid = PR_FALSE;
+        
+#ifdef DEBUG        
+        char warnBuf[1024];
+        sprintf(warnBuf, "Bad font metrics for: %s err: %8.8x", NS_ConvertUTF16toUTF8(GetName()).get(), PRUint32(err));
+        NS_WARNING(warnBuf);
+#endif
+        return;
+    }
 
     if (atsMetrics.xHeight)
         mMetrics.xHeight = atsMetrics.xHeight * size;
     else
         mMetrics.xHeight = GetCharHeight('x');
 
     if (mAdjustedSize == 0.0f) {
         if (mMetrics.xHeight != 0.0f && GetStyle()->sizeAdjust != 0.0f) {
@@ -416,20 +433,23 @@ gfxAtsuiFont::GetCharHeight(PRUnichar c)
 
     ATSUDisposeTextLayout(layout);
 
     return rect.bottom - rect.top;
 }
 
 gfxAtsuiFont::~gfxAtsuiFont()
 {
-    cairo_scaled_font_destroy(mScaledFont);
-    cairo_font_face_destroy(mFontFace);
+    if (mScaledFont)
+        cairo_scaled_font_destroy(mScaledFont);
+    if (mFontFace)
+        cairo_font_face_destroy(mFontFace);
 
-    ATSUDisposeStyle(mATSUStyle);
+    if (mATSUStyle)
+        ATSUDisposeStyle(mATSUStyle);
 }
 
 const gfxFont::Metrics&
 gfxAtsuiFont::GetMetrics()
 {
     return mMetrics;
 }