Dear Hans,
I have a hard time following your explanation, especially of the word »bundle«, because I'm not certain whether that refers to LaTeX packages or one of TextMate's LaTeX bundles. The initial problem you describe has *nothing* to do with TextMate: it appears your file was saved in the wrong encoding (not applemac), so latex cannot decipher non-ASCII characters such as umlaute or accented characters. By default, TextMate and pretty much all other editors use UTF8, hence my advice to *change* the argument for when you load the inputenc LaTeX package to UTF8:
\usepackage[utf8]{inputenc}
If you comment out this usepackage command, pdflatex will not be able to correctly render non-ASCII characters (e. g. ä, ö and ü).
Unfortunately the problem with the example code you've included is that it cannot be used to detect problems with file encodings. But the mail you've sent indicates that it's just a file encoding problem that's easy to solve (e. g. the umlaut for »für« was not copied correctly from your text editor). I think what you've been missing is Step 2 below.
I recommend you the following: (0) Open the problematic .tex file in TextMate (1) Change \usepackage[applemac]{inputenc} to \usepackage[utf8]{inputenc}. (2) Select Save As from the File menu and make sure that UTF8 as file encoding is selected. Then proceed to save the file as text.tex someplace else. This way any experiment with LaTeX will not destroy work. (3) Try to compile the document.
Note that if you load other LaTeX files via \include{filename.tex} or \input{filename.tex}, check that the other files are also all saved in the correct encoding, UTF8!
If it doesn't work out, please include the content of test.log (in general: [document name].log) in your next post.
Max