You can look unfamiliar with a language without having another language's accent.

I don't really understand what your definition of accent is then ;-)

For me it's using one language in a non-idiomatic manner because your approach to solving problems has been pushed in one direction by another languages idioms.

For example, I'm not avoiding meta-classes in CLOS because I'm unfamiliar with the concept. I started learning OO with CLOS and other languages that supported meta-classes long before I came across Perl. I'm avoiding them because I've spent a lot of time coding type in Perl over the last few years, and Perl doesn't support classes in the same way as other OO languages.

Another example is when I started learning Ruby. I definitely wrote Ruby with a Perl accent for some time before I learned the more natural Ruby idioms. I had people comment on that fact because I was doing things like explicit loops rather than using iterators/continuations.