And in some stock 6.5 ROMS you have to enable it in the registry:
.Net Framework 3.5 tweak for wm 6.5 roms
after 3.5 insatalld it doesnt seem to become active in the 6.5 rom.
in the registry it will show off and you have to manually turn it on.
heres how.. reg editor needed...(i use ce reg editor because it is
installed on my comp and not my phone not taking up ram)
HKLM\Software\Microsoft\.NETCompactFramework
change 2.0.7045.00 from 1 to 0
change 3.5.7283.00 from 0 to 1
wait appx 30 sec... then just soft reset the phone
hope it helps props to modaco peeps for confirmation...and
www.samsung-omnia.org