tbitmap with mask

[dcelso]

Any one can tellme how to do a 24 bitmap with a 8 bits mask array? I need it To simulate an alpha channel in 24 bits mode.
Tbitmap have a maskhandle but i don't know how to use those property. Seems to use a hbitmap 8bits gray scale (or 1 bit). But how can i create it to use as maskhandle.