Can I jailbreak an at&t Iphone 4 with ios7 installed?

I know they don't have a jailbreak out yet for ios7, is there some way I can un install ios 7.0.2
any info would be helpful. I bought the phone a few days ago on ebay and never thought to ask what version of ios it was running on. I'm looking to jailbreak then unlock so I can use it on Straight Talk

You need to wait for a month or so…
Because develpers need sine time to jailbrake new ios 7
Some rumers are that ios 7 will not be jailbroken!
Patience is ehat the key now!
Hope it works!
10 points

No you can't jailbreak it nor downgrade.

Even if there was a jailbreak that does not guarantee an unlock would be available.