Hi Camu,
I've been toying with the results.
First, to any future reader of this post, camu replied to me by email:
I've been trying to debug your template, and finally I found the culprit. If you go Appearance >Atahualpa Theme Options > Comments (left column), you'll see there's an option which says
Allow comments on "Page" pages, too?
This option is currently set to 'Yes', and if you change it to 'No', comments will disappear from the management page. As I thought, it was a problem with your template, not the plugin. I have left this option set to 'No'. Please let me know if you have questions...
I have to say, I can't understand this, but: after reading your response, I was perplexed: why did I see the problem on other themes, after all? However, I deliberatly wanted comments on pages too, so I turned it back on, and strangely: now if you go to the subscribe page, even with the comments on pages turned back on, it now is fixed (though it does say "comments closed" at the bottom of the subscribe pages). In short, I'm perplexed that turning the switch you turned off back on does not reintroduce the problem. I'm equally perplexed that the problem presented itself on other themes but no longer does. Very strange.
I would say, if your plugin doesn't allow page comments ordinarily (although it is now seemingly allowing this on my site), that it should.
I should note, I added this to my code to test what wordpress thought of your manage subscription pages:
<?php
if ( is_single() ) { ?>
<H1>SINGLE</H1>
<?php }
if ( is_page() ) { ?>
<H1>PAGE</H1>
<?php } ?>
The result was that WP thought it was a page, not a post. Strangely, it follows my permalink structure for posts: blog.com/info/comment-subscriptions/?query
whereas my pages have distinct names usually: blog.com/about/ for example.
Since the page does not really exist that this info appears on, it seems one cannot isolate it to choose to discard comments from that page. I wish the plugin would point to some blank real page, which would be very helpful.
On a side note: a few tweaks I'd like to see:
1) wish either the email textbox had no value or otherwise when you clicked it the "email" disappeared using javascript;
2) wish the name of the article on the subscription management page was a link back to the article, and that a link back existed after someone subscribes without commenting;
3) there's no obvious way for a user to get into the subscription page after they've confirmed their email address, except when a new update is emailed to them. This doesn't bother me much though, but if I turn off the double-opt-in email option, a user has no way of getting this info until they get an update. Perhaps then, with double opt-in turned off, a user should still get an update when the subscribe, telling them they've successfully subscribed (or at least make it an option).