> Does anyone have this combination? How big does it make the IPAQ? 
> (specific dimensions if you have them)
>

I apologise that this doesn't exactly answer your question but I have a 3600 with a 802.11 CF card to hand and someone near me said that they were similar.

The 3600 CF sleeve makes the IPAQ roughly 26x86x131mm.  More interesting for you (if the 3150 CF sleeve is slightly different) is the Linksys Instant Wireless CF card as an example.  This adds 35mm to the height but is inside the other sleeve dimensions.

Mike