I checked the behaviour for isImagePage on a different installation of ZenPhoto (wete.org). I searched for 'e', what is quite stupid, but it leads to many results. ;-) I got 3 pages with albums, page 4 is mixed, page 5 ff. contains only images. Page 1 and 2 isImagePage returns false (correct behaviour). But on page 3 (only albums!) it returns true. In my first example (see above) there were only 2 pages of albums (page 1 pure, page 2 mixed), so I think, the error could be descriped as "works fine exept on the page BEFORE the first page with images".
Now I will install the nightly build and check this again.
But now there is another error:
Warning: array_slice() expects parameter 1 to be array, boolean given in /........./galerie/zp-core/class-search.php on line 1378
See:
http://www.wete.org/galerie/page/search/e/4
(at the bottom)
I also checked it in the default theme: same error.
Wete