TYPO3 Core

When creating a menu, if the TS setup for the NO state is copied to the ACT state, the menu item is no longer detected as active.

The following script works fine

lib.test = HMENU
lib.test.1 = TMENU
lib.test.1 {
wrap = <ul id="navlist">|</ul>
NO.allWrap = <li>|</li>
ACT = 1
ACT.allWrap = <li class="act">|</li>
CUR = 1
CUR.allWrap = <li class="cur">|</li>
}

When modified as such (it doesn't make any real sense, but it's an example that shows the problem):

lib.test = HMENU
lib.test.1 = TMENU
lib.test.1 {
wrap = <ul id="navlist">|</ul>
NO.allWrap = <li>|</li>
ACT = 1
ACT < .NO
ACT.allWrap = <li class="act">|</li>
CUR = 1
CUR < .ACT
CUR.allWrap = <li class="cur">|</li>
}

The active item is not marked at all. From debug output I set in tslib_menu::isActive() this method was not even called, which is really weird.

Typo3 version: 4.0 and 4.0.2
PHP version: 5.1.2 and 5.1.4
(issue imported from #M4499)