safe to JB if i'm using GEVEY?!

[Omarsafadi]

my iPhone 4 is not factory unlocked.. i unlocked it using GEVEY sim... i want to know if it is safe to JB and not effecting the unlock..

also check this link out please :
How to use Gevey Ultra Sim | Iphone 4 Jailbreak.org

is this real? does it work? i don't know if my GEVEY is ultra or not tho.
thank you in advance.

 

[Omarsafadi]

Ok i jailbreaked and it works like a charm.. So there u go guys it works..