iPhone 4 proximity sensor causing cheek hangups?

Some more issues are popping up with iPhone 4 users. Seems the proximity sensors are a little less sensitive than their predecessors, causing hang-ups from people who hold the iPhone close to their ear, move it slightly away and then touch their cheek to it.   Also some people are muting by accident.  Apple discussions are growing.

Is this another iPhone 4 issue or just a learning curve thing?  We’re not getting this problem but it is apparent that many people are having the issue.

9to5mac reader, Christopher Menendez writes:

Yesterday, after camping out 13.5 hours in jacksonville, a 2 hour drive from Tallahassee where I’m currently attending FSU, I noticed my calls were hanging up out of nowhere. I didn’t attribute this to the antenna problem because not only do I have a bumper but the call also did not show up as failed, merely as hung up (would return me to my recent calls page). I then started thinking i might be cheek dialing…a quick call to moviefone to give me a chance to mess with the proximity sensor using my hands showed it is COMPLETELY out of wack. It takes too long to turn off once you put it to your face (thus hanging up on people with my cheek) and would turn on immediately after pulling it away from my face half an inch. A quick search on google and the macrumors forums show that many people are experiencing the problem