V60 not working with replacement antenna

I broke the antenna in my V60 (TDMA, on ATT/Cingular network). I got a
replacement bushing and fixed the problem. However, my phone now has
weaker reception that fluctuates a lot - switches between digital and
analog, often goes into roam. Even worse, it won't take or place calls
anymore, even when it shows that it's got a couple of bars in terms of
reception strength. I was able to make a call to it a couple of times
out of a few dozen attempts, but obviously this is not good.

Any ideas? Is there something that could've been broken at the same
time the antenna was? The phone seems fine on the inside.

Thanks. Nikita.