Is it possible to select the CF version in the next version?

Hello, tonight I discovered a tip, I noticed that some Referrence are not recognised like "System.IO.Compression" (for create and read any ZIP file) coz on CF2.0 it didn't exist but in 3.5 yes so I copied System.dll from V3.5 folder to V2.0 in overwriting and now it's working well...
So maybe it's possible to make a parameter on the B4P project file for select the compact framework to use and check if it's installed on the desktop...

Thanks for your replie!