Will jailbreaking my iPhone reset the lock?

I have an iPhone 3gs that was on contract with vodafone, who asked for the iphones IEMI thingy, and i have had it unlocked by them for a fee and i'm just wondering if i jailbroke my phone would it reset the unlock so it can only be used on vodafone? (currently using an o2 sim)

Jailbreaking only unlock your 3 party software lock if you using jail-breaking you can access 3 party software. If you want use any sim you must need network unlock your iphone. You can unlock your iphone 3gs at http://www.theunlockarena.com/apple-iphone-3gs/rs13wp9.