Youtube tutorial on Parking a call using the GXP20xx series phone

Direct Link: http://www.youtube.com/watch?v=U5XlrBfznqk

Here are the steps:

1. Do not place call on hold  
2. Press line 2 and dial 99  
3. Once you hear which line the call is parked on press the transfer button  
4. Then press Line 1 to complete the transfer