Installation:

1: Install this mod:
https://www.gtainside.com/en/gta4/airplanes/84004-airbus-a319/

2: Extract the contents of this archive

3: Replace the "a319.wtd" file with either the one in the "T-Mobile" folder for the T-Mobile livery or the one in the "T-Com" folder for the T-Com livery

Credit for Airbus A319 goes to udihow. Credit for the liveries goes to Stefan Leppek. Converted from FS2004 to GTA IV by yours truly.