zero-width spaces problem - table cell contents overfl

Hi all,
i'm attempting to overcome the problem of table cell contents
overflowing by inserting zero-width spaces into the content string. The
scheme is working correctly in that i know longer receive overflow
errors. Unfortunately the zero-width spaces are being rendered as
visible white space such that  www.urlname.com becomes www. urlname.
com.  My xsl try to replace the '.' with '.​' which should give
me the url without the spaces.
Has anyone encountered this problem before? any suggestions as to why
the zero-width spaces are being rendered as visible white space??
any help appreciated!

Regards
Paul.

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