my rhel5 gnome desktop is not comming automatically on boot
 

To speed up my rhel5 system booting I removed sendmail and sm-client.
Since then I'm not getting my gnome desktop automatically except task bar and a black screen. Surprisingly,clicking on Trash on the taskbar I'm getting the desktp and icons etc. What mighit be the reason ?

Sounds like it removed desktop stuff as a dependency of sm-client...
You could try extracting the stuff from the Trash bin. I think(?) there's a right-click option on the Trash bin to do that.

If that doesn't work, you could try re-installing desktop using

yum groupinstall "GNOME Desktop Environment"