Hi bluevolume,
We hit this problem too, but we were using MOSS (SharePoint) so we could leverage that for picking users. You can create a smart object that consumes the SharePoint service object for a site instance and retrieve all users that are members of a sharepoint group or site or whatever. Is this something that might be of interest to you?
I would certainly advocate the use of ASPX over Infopath as our customers prefer the slick branded forms and our developers prefer to 'hack' code (as the posibilities are endless!) rather than work with rules (limiting and frustrating!).
Martin
Martin Allen
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