Subclassing error

Hi,

I am trying to subclass a button using the SetWindowSubclass() function but it tells me that 'the identifier was not found'. I have included "commctl.h" and added comctl32.lib to the linker command line. I also had a look in comctl32.lib and found the word SetWindowSubclass. I assume this means I have at least version 6 of the library which is required. Why would this error still come up? What could I be doing wrong?

Maybe I'll have to use SetWindowLongPtr()....

Thanks,

Philipp