Losing 'new posts' markers
 

i've noticed that whenever i reply to a post and then return to the top of the forum (by clicking on the simply maya link in the forum tree or the forum link at the top of the page) that all the 'illuminated' light bulbs informing me of new posts in that section go back to clear bulbs... for ALL sections, except for the one i just posted in. i DO have cookies enabled (or else i don't think it would be able to tell me where new posts were when i first get onto the forum).

any explanation, or should i just ignore it? it's not really annoying, just a curiosity of mine.