Imagelist icon's maskcolor turn black

HI
I load few .ico files in imagelist - 16x16. When I look those icons in explorer they are OK and mask color is OK. I use this toolbar control (like in IE without borders) with imagelist object bound to it. The problem is when and load aplication sever times. Icon's maskcolor becomes black.
I tried a lot of different things e.g. icons are in all paletes: 16,256,true colors. Nothing seems to work...
Any ideas, what could be wrong?

thx,
Rok

Ghastly isn't it. Don't use icons. Use bitmaps and everything will be just fine.