PDT (not PHPEclipse, already you know) editor is based on WST, and WST
does not support Highlighted annotation. So you cannot change the color of
Debug Current Instruction Pointer. (You can choose Squiggles.)
(Also you cannot see any other Highlighted annotations such as Search
Results)
(This bug will be fixed on Eclipse3.4-wst 3.0-pdt 1.1)