I believe it is because ${requestScope.map.c} returns "42". Since "42".equalsIgnoreCase("true") == false, ${not requestScope.map.c} == true.
Sorry i could not understand the explanation above(in Bold)..if i had missed any topic related to this in HFSJ please tell me the page number so that i can go back and read once again..
Thanks & Regards,
Sudhakar Karnati