[xml] date-time strangeless last night

["Christopher R. Palmer" <crpalmer vivisimo com>]

Last night, date:seconds() started returning invalid values. To test I 
created a simple stylesheet that simply printed

<xsl:value-of select="date:seconds()"/>

It printed a time from the day before.  Coincidentally, this started 
happening after 8pm EDT which would be when my time was in September and 
the GM time was in October.  The code (line 791 of 1.1.17) looks pretty 
suspicious to me:

    ret->value.date.tzo = (((ret->value.date.day * 1440) +
                            (ret->value.date.hour * 60) +
                             ret->value.date.min) -
                           ((gmTm->tm_mday * 1440) + (gmTm->tm_hour * 60) +
                             gmTm->tm_min));

which seems to be computing the seconds between localtime and gmtime.  With 
no mention of month I can't see how that is right...  I assume something 
similar but worse will happen at the end of the year.

I can reproduce this problem by adding

secs = 1159664596;

immediately after the call to time(NULL) in exsltDateCurrent while running 
the software on a machine in EDT.  When I do this, the value of tzo is 2000 
while the correct value should be -240.

Cheers,
Chris.