std::string.assign crashes in gcc 4.1.2...help me

[dbabu]

Hello all
Our gcc binary was ported from version 2.95 to 4.1.2 . Now the following call to string.assign crashes with no clues . Can anyone please throw light on this..?
Here strMacAddress is std::string type and macAddress is char[18] ..

strMacAddress.assign(macAddress); <--- crash here ..

Is there anyway I can analyse the situation in right direction ?

Thanks in advance
D babu

[Roxoff]

Is macAddress null terminated correctly?

What happens if you try the assignment operator, e.g.

strMacAddress = macAddress;