Look at Unicode::String, to see if this gives you anything you can use.

If you are using the term "unicode" to refer to "ucs2" or "utf16" (i.e. full 16-bit unicode encoding, as opposed to utf8, which is variable-width encoding), then one thing that might be screwing you up is byte order. Does your existing utf16 use network (big-endian) or wintel byte order? (Do the unicode strings start with byte-order marks?)

What do you mean by "garbage"? Is it that your perl script cannot display the unicode strings in any intelligible manner, or is the data getting "updated" or "rearranged" or otherwise "filtered" in some inappropriate way? Do you want to keep everything in unicode, or would you rather convert to ANSI?

If you'd like folks to send you answers rather than questions, give us some snippets of code, and some input and output that illustrate the problem.

UPDATE: Forgive me, that last bit was unfair -- I haven't tried posting unicode data to this site yet, and it may not be all that easy to do. But a sample of code that illustrates what you are trying to do would be very helpful, as well as some additional detail about what the source data looks like (e.g. give us a short string of byte pairs in hex notation), and a better idea of what your script is producing, and what you actually want it to produce.