Search the path for krb5-config if the prefix wasn't specified.
Created attachment 1685 [details] Patch solving the problem
Looks reasonable. The AC_PATH_PROG also provides output so the AC_MESSAGE_CHECKING and AC_MSG_RESULT lines are superfluous. Applied, thanks. It will be in 5.3p1.
Mass move of RESOLVED bugs to CLOSED now that 5.3 is out.