Make phone running Android 2.3.3 re-download configuration settings from ISP
According to this page you can obtain your provider settings by sending an SMS with just the word "Five" to 2211. Most providers have a number you can send text messages to in order to receive the settings again.

If that fails, you can try to manually configure your access point to use the following data (taken from this page):
Navigate to Settings > Wireless &amp; networks > Mobile networks > Access point names, then press the menu button and select "New APN". Then enter:


Name:      Etisalat
APN:       wap
Proxy:     *not set*
Port:      *not set*
Username:  *not set*
Password:  *not set*
Server:    *not set*
MMSC:      *not set*
MMS Proxy: *not set*
MMS Port:  *not set*
MCC:       413
MNC:       03
Authentication type: None
APN type:  default,supl
APN protocol: IPv4


Then press the menu button and select save.

If that doesn't work either, you can find a lot of alternate configurations on this page.