Once you get the extra LUN allocated then you need to extend the VG
woth whatever means you feel ( Eg: extendvg or extendvg4vp ) . Then you
need to manually allocate the new PPs to each LV you wish . How can a
VG know a bt our request ..

For adding for space for an LV you can use chfs command
Synatx looks like : - chfs -a size=+<number>M <fs name>

Hope this clarifies you ...