I may know what is going on, but it will take a little explaining. When I started reading your post, I said to myself "I wonder if he/she is using a tab control?". Almost before the thought ended, I read that you were using a tab control.
I wrote a PDA application with a non-oversized tab control with multiple tabs. As I kept adding functionality, I kept adding tabs. Eventually, I added a tab, and the line showed up. At the time, though, I didn't realize the cause. I even showed the application to a integrator who worked on PDA stuff, and he could not explain it. As it turned out, if I shrunk the font size of my tab text, the line went away. Now even when the "problem" tab was added, it did not extend beyond the right boundary of the tab control on the PDA, PDA emulator, or PC version, so I think it is a bug of some sort. I needed to leave about 15% of the entire width of the tab control free, so that the the left side of the first tab to the right side of the last tab was no more than 85% of the tab control width.
I suspect you are having the same sort of buggy issue with your tab control. I have no proof, but just a strong gut feeling based on my experiences. Do you have titles on your tabs? if so, try shrinking the font. If not, maybe you need to have titles on your tabs. Who knows? Hopefully someone from NI will respond with a real solution.
Lots of luck,
Ed DeWitt
