unable to start ArcSDE service

[SyedMasood_Khadri]

Hi

I have installed Arc SDE 10.1 on windows 2008 server and our Oracle 11g Release 2 is running on Linux.
I have created Arc SDE service succesfully with create service command.
But when i try to start the service from windows control panel, i get following error:

Windows unable to start ArcSDE service, Error 1053, unable to start the service in timely fashion.

please help

[SyedMasood_Khadri]

Thanks to all for your suggestins.
I will install 64 bit oracle client and get back to you.