what is the correct filter for that ?

[cdkiller]

hello,

i have an opendialog box.

and i want to use the "Filter" option but not like

textfiles *.txt
all files *.*

it should be so

textfiles *.txt *.doc *.rtf
all files *.*

dou you know what i mean ?
i want two extensions for one entry which are shown in the explorerbox.

thanks

Regards,
cdkiller