No. iPhone 4s can only be jailbroken on 5.0.1

Please read the first post and it will tell you most of the necessary information.

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Added on March 11, 2012, 12:47 pm

Use TinyUmbrella, in the advance tab you can tick the box that says "Retrieve SHSH from Cydia"

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Added on March 11, 2012, 12:50 pm
You need to get the SHSH from Cydia first to your local drive --> Use TinyUmbrella

Then follow the first post with regards to downgrading (I know it's counter intuitive but downgrading/restoring/upgrading to a firmware that Apple no longer signs follows the same route).

I am not sure if Cydia saves the APTicket (unlike TinyUmbrella and iFaith) so I give it a 40-60 chance that it will work (I don't think it will work ..)

There is always the tethered jailbreak option if anything goes wrong with the process you're doing.