I contributed the following to FAQ - CapFAQ a long time ago, and since that page has received over 4,000 views I thought it might be worthwhile to post it here. Although originally intended for Captivate users, it's applicable to the Skyrocket, too. FYI, default ring time: 20 seconds. This procedure increases the ring time to 30 seconds. Enjoy!
Extending the length of time your phone rings before rolling over into voicemail...
1. On your phone, dial *#61# and place the call.
2. Following information should be displayed: number that the calls are being forwarded to and the delay before the forwarding engages.
3. Write down the number (including +1)
4. Dial **61*+1xxxyyyzzzz*11*30# and hit Send. +1xxxyyyzzzz is the number you wrote down previously, 30 is the delay in seconds. The delay can be set in 5 second increments, 30 is maximum
5. Dial *#61# to verify that the new settings are active.
Note: I am not the original author of this procedure. If I knew its origins, I'd provide appropriate credit.
Extending the length of time your phone rings before rolling over into voicemail...
1. On your phone, dial *#61# and place the call.
2. Following information should be displayed: number that the calls are being forwarded to and the delay before the forwarding engages.
3. Write down the number (including +1)
4. Dial **61*+1xxxyyyzzzz*11*30# and hit Send. +1xxxyyyzzzz is the number you wrote down previously, 30 is the delay in seconds. The delay can be set in 5 second increments, 30 is maximum
5. Dial *#61# to verify that the new settings are active.
Note: I am not the original author of this procedure. If I knew its origins, I'd provide appropriate credit.