Break the code!

[ronthepon]

I thought I'd begin a thread for code breaking (as I specially enjoy doing them in times of stress)

So, here goes.

Can you break:

vgzs zqd xnt fnhmf sn cn snczx

For a hint,

'on air'
converts to
'nm zhq'

I'd expect it gets very easy now.

[ughaibu]

Your clue is too complete, "what are you going to do today".
Have you heard of the Voynich manuscript? http://www.voynich.com/folios/

[Jay-qu]

how bout this one:

Omnspanarhsmon Klifbsilib cpar btibarmnhepbemn!

Clue: A = H

[ronthepon]

Naturally, the first code is supposed to be ultrasimple.

Now try

snevo nepo ni taem neerg

This is also very simple.

[ronthepon]

Oh, you've already put one up, JQ. I'll try it first...

[ughaibu]

"Green meat in open ovens".

[Jay-qu]

Its reversed

[ronthepon]

well put smiley.

[ughaibu]

Jay-qu: Does A equal H both to and from normal and encrypted?

[Jay-qu]

encrypting A -> H, hence decrypting H -> A, but like english there are exceptions to the rule.

I made this cypher up and it will be very hard to break - Im not sure if I want to give the answer up at all, but if you solve it I will tell you if its correct. hence this could be potentially frustrating