This problem bugged me for a long time. The trouble is that sometimes, the Menu key doesnt work, requiring me to restart the mobile. Like, when I had this long SMS typed and the phone went into Lock mode. When I unlocked, Menu key aint working and I couldnt send the message. And I got really pissed off.
If you are unlucky enough to have this prob too, dont worry. You are lucky that you found this page. :)
Enough babbling. On with the solution.
Step 1. Press the Power button at the top once to open the options menu.
Step 2. Select 'Lock Phone' option.
Step 3. Unlock with your lock code. (Default is 12345)
Step 4. Press the 'Menu' key.
Step 5. Smile :)
That was really simple, huh?