<p>The upstream version that was picked contains characters that
are invalid in Debian version strings.</p>

<p>For version strings that come from upstream tags, this can
be because the upstream tags use characters that are not valid
in Debian version strings. The janitor currently only applies
very basic version mangling to upstream tags:

<ul>
    <li>Strip <i>release-</i> prefixes and <i>-release</i> suffixes</li>
    <li>Strip <i>package-</i> prefixes</li>
    <li>Strip <i>v</i> prefixes</li>
    <li>Replace any underscores with dots if there are no other
    dots in the version. This is done for compatibility with CVS style tags,
    which usually did not use dots.</li>
</li>

<p>For version strings that come from uscan, no additional mangling
is performed besides the mangling that uscan already does.
</p>

<p>In some cases, the version string matching is overly broad - and the
lintian-brush could possibly replace the first group with @ANY_VERSION@ to
fix the watch file.</p>

</p>
