[CS3] runtime error 2022 question

[loriwang]

Hi All, we face a problem in development which cause runtime error 2022. We have a button in libaray which has bitmaps for Up, Over, Down. We want to link these bitmaps to actionscript to make some changes on the bitmapdata. But when this button first added onto stage it will cause runtime error 2022. We even tried add movieclips to encapsule these bitmap and add movieclip in the button. The error still there. Is any way to bypass this problem? Or any document about error 2022? I searched in google but all what I can find is a simple explaination same as which in flash doc.

[UncleNinja]

Sorry, I don't magically know error numbers. :p (kidding)
What is the full text of the error? :)

[loriwang]

Sorry, the description of runtime error 2022 is "Class _ must inherit from DisplayObject to link to a symbol".

[the binary]

looks like your class has to extend the DisplayObject-class..