diff --git a/gui/slidervalue.cpp b/gui/slidervalue.cpp
index 5b4d57f..700d7d5 100644
--- a/gui/slidervalue.cpp
+++ b/gui/slidervalue.cpp
@@ -198,7 +198,7 @@
 		}
 	}
 
-	gr_getFontDetails(mFont ? mFont->GetResource() : NULL, (unsigned*) &mFontHeight, NULL);
+	mFontHeight = gr_getMaxFontHeight(mFont ? mFont->GetResource() : NULL);
 
 	if(mShowCurr)
 	{