Since we already have the define ISC_STATUS_LENGTH for the the length of
the status vector, we should use it! Replaced 'status[20]' with
'status[ISC_STATUS_LENGTH]'.
Replaced the different symbolic names for the maximum length of a path
(MAX_PATH, MAX_PATH_LENGTH, MAXPATHLEN) with one uniq symbol MAXPATHLEN.
o check for the availability in configure
o check for the number of arguments in configure
o synchronised config.h.in and MSVC pendant
NOTE: If you have problems on your system, don't change the source.
Extend the tests in configure.in!!!
