cant install 3rd party apps through itunes 8

[mat_cal1999]

hi i've had my iphone 3g for a week now and i'm still getting my head round it all.

i've jailbroke my phone and it all works fine until i try and install an application from my pc rether than through installer.app

i can import them into itunes but when i sync it says the application could not be verified

any help would be fantastic
thanks in advance
mat

[jamesus]

Are you trying to load cracked apps?