To mount a windows share from an AIX server it’s needed the CIFS support to be installed.
If Your server /sbin/helpers directory contains a file called mount_cifs no problem
ls -l /sbin/helpers
total 488
-r-xr-xr-x 1 root system 33198 Jul 13 2010 aufsmnthelp
drwxrwxr-x 2 root system 4096 Apr 15 2010 jfs2
-r-xr-xr-x 1 root system 23224 Jul 13 2010 mount_cifs
-r-xr-xr-x 1 root system 35638 Jul 13 2010 nfsmnthelp
-r-xr-xr-x 1 bin bin 6268 Dec 18 2009 udfmnthelp
-r-xr-xr-x 1 bin bin 138292 Dec 18 2009 v3fshelper
Otherwise You need to install it.
Then You can try to mount the Windows share using the mount command, specifying the cifs filesystem, the node name/IP, username, password and so on…
mount -v cifs -n node/username/passw [-o options] /winshare /directory
e.g.
mount -v cifs -n 192.168.1.28/george/HareKrishna \
-o wrkgrp=BEATLES,fmode=755 \
IndiaPics /opt/holidays/meditation/india1967