Index: /FCKeditor/trunk/editor/_source/classes/fcktoolbarfontformatcombo.js
===================================================================
--- /FCKeditor/trunk/editor/_source/classes/fcktoolbarfontformatcombo.js	(revision 1006)
+++ /FCKeditor/trunk/editor/_source/classes/fcktoolbarfontformatcombo.js	(revision 1007)
@@ -73,6 +73,11 @@
 		var elementName = elements[ i ] ;
 		var style = FCKStyles.GetStyle( '_FCK_' + elementName ) ;
-		style.Label = oNames[ elementName ] ;
-		styles[ '_FCK_' + elementName ] = style ;
+		if ( style )
+		{
+			style.Label = oNames[ elementName ] ;
+			styles[ '_FCK_' + elementName ] = style ;
+		}
+		else
+			alert( "The FCKConfig.CoreStyles['" + elementName + "'] setting was not found. Please check the fckconfig.js file" ) ;
 	}
 
Index: /FCKeditor/trunk/editor/_source/classes/fcktoolbarfontscombo.js
===================================================================
--- /FCKeditor/trunk/editor/_source/classes/fcktoolbarfontscombo.js	(revision 1006)
+++ /FCKeditor/trunk/editor/_source/classes/fcktoolbarfontscombo.js	(revision 1007)
@@ -44,4 +44,10 @@
 	var baseStyle = FCKStyles.GetStyle( '_FCK_FontFace' ) ;
 
+	if ( !baseStyle )
+	{
+		alert( "The FCKConfig.CoreStyles['Size'] setting was not found. Please check the fckconfig.js file" ) ;
+		return {} ;
+	}
+
 	var styles = {} ;
 
@@ -55,4 +61,5 @@
 
 		var style = FCKTools.CloneObject( baseStyle ) ;
+
 		style.SetVariable( 'Font', font ) ;
 		style.Label = caption ;
Index: /FCKeditor/trunk/editor/_source/classes/fcktoolbarfontsizecombo.js
===================================================================
--- /FCKeditor/trunk/editor/_source/classes/fcktoolbarfontsizecombo.js	(revision 1006)
+++ /FCKeditor/trunk/editor/_source/classes/fcktoolbarfontsizecombo.js	(revision 1007)
@@ -28,5 +28,5 @@
 	this.Tooltip	= tooltip ? tooltip : this.Label ;
 	this.Style		= style ? style : FCK_TOOLBARITEM_ICONTEXT ;
-	
+
 	this.DefaultLabel = FCKConfig.DefaultFontSizeLabel || '' ;
 
@@ -45,4 +45,10 @@
 {
 	var baseStyle = FCKStyles.GetStyle( '_FCK_Size' ) ;
+
+	if ( !baseStyle )
+	{
+		alert( "The FCKConfig.CoreStyles['FontFace'] setting was not found. Please check the fckconfig.js file" ) ;
+		return {} ;
+	}
 
 	var styles = {} ;