^^OK, I've solved my problem, and this may help others as well.
I was only looking at the "Last Comments" page as an anonymous user to determine whether it was working properly. What I eventually figured out was that it WAS blocking spam comments from being shown with individual pictures, but not on the "Last Comments" page.
Since this is the page my wife tends to view most often, it was important to me to get this fixed.
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DISCLAIMER:
I'm NOT a PHP or SQL Expert.
I'm NOT EVEN a PHP noob.
The only testing that was done was that this fixed MY problem on MY Coppermine 1.4.10 install.
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It appears that the comments shown on the "Last Comments" page are queried from the section of code that begins on Line 963 of functions.inc.php (in /include)
I made very minor changes to two queries in this section, and it seems to have fixed the problem.
The first is on Line 979
The ORIGINAL, UMODIFIED QUERY:
$query = "SELECT COUNT(*) from {$CONFIG['TABLE_COMMENTS']}, {$CONFIG['TABLE_PICTURES']} WHERE approved = 'YES' AND {$CONFIG['TABLE_COMMENTS']}.pid = {$CONFIG['TABLE_PICTURES']}.pid $TMP_SET $keyword)";
All I did was ad an "AND" to check that is_spam=0. If you don't change this query, your spam comments will still be masked, but it will count ALL the records, and show you empty pages where the spam comments would be.
Modify the above query to match this:
$query = "SELECT COUNT(*) from {$CONFIG['TABLE_COMMENTS']}, {$CONFIG['TABLE_PICTURES']} WHERE approved = 'YES' AND {$CONFIG['TABLE_COMMENTS']}.is_spam = 0 AND {$CONFIG['TABLE_COMMENTS']}.pid = {$CONFIG['TABLE_PICTURES']}.pid $TMP_SET $keyword)";
One more query to do. It's on line 993. This is the one that actually loads the comments (vs counting the comments it intends to load).
This is the ORIGINAL, UNMODIFIED QUERY:
$query = "SELECT $select_columns FROM {$CONFIG['TABLE_COMMENTS']} as c, {$CONFIG['TABLE_PICTURES']} as p WHERE approved = 'YES' AND c.pid = p.pid $TMP_SET $keyword) ORDER by msg_id DESC $limit";
Again, I just added an AND. Modify it to match this:
$query = "SELECT $select_columns FROM {$CONFIG['TABLE_COMMENTS']} as c, {$CONFIG['TABLE_PICTURES']} as p WHERE approved = 'YES' AND c.pid = p.pid AND c.is_spam = 0 $TMP_SET $keyword) ORDER by msg_id DESC $limit";
I don't know enough to know whether it will be in exactly the same place on every install, nor whether functions.inc.php is the same on every 1.4.10 install, so that's why I thought it would be better to just post exactly what I did. It does, however, work.
Joe