...For WWW: A php example, that uses fast Unix pipes (and no disk write permissions required on the host), is provided.
It support UTF-8 (Russian, etc.).
Proper escaping functions are provided in the php example.
Well known pdftk utility can be used for filling in PDF Forms.
However, I was not able to get the version pdftk1.4 to work with UTF-8.
It's XFDF format support UTF-8 encoding, and assumes Adobe uses an UTF-8 font by default. Whereas, Adobe Readers (at least upto version X) do not, and UTF-8 text is entered by pdftk but is not shown in its form until user clicks on the form and edits it.
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