There are multiple ways omnipotence is described. (The following is taken from Wikipedia (
http://en.wikipedia.org/wiki/Omnipotence_paradox))
1. "Y is absolutely omnipotent" means that "Y" can do everything absolutely. Everything that can be expressed in a string of words even if it can be shown to be self-contradictory, "Y"is not bound in action, as we are in thought by the laws of logic." (position taken by Descartes)
2. "Y is omnipotent" means "Y can do X" is true if and only if X is a logically consistent description of a state of affairs. (position take by Thomas Aquinas)
3. "Y is omnipotent" means "Y can do X" is true if and only if "Y does X" is logically consistent. (another position taken by Aquinas)
4. "Y is omnipotent" means whenever "Y will bring about X" is logically possible, then "Y can bring about X" is true.
5. "Y is almighty" means that Y is not just more powerful than any creature; no creature can compete with Y in power, even unsuccessfully. (advocated by Peter Geach)
The only one of those that follows the actual definition of omnipotence is the first.
The idea that god is omnipotent. but cannot do anything that makes him not omnipotent. is in my opinion a mental cop out. (#2-#4)
Your definition of Omnipotent in this thread follows the last formulation (#5), which is not really omnipotence, but a lesser characteristic known as being "almighty".