Data folder in differnet filesystem

I have 2 doubts related to Filsesytem and Postgres data folder

1.Currently in CentOS, our postgres data folder is in single filesystem. Is
there any possibility to have a single data folder of single postgres in
more then one file system.
2.I am having three big DB, is it possible to have a data of each DB in
different file system. so if i want to add a DB to postgre i will mount a
drive (filesystem ) and point that location for the postgres to use that
space.
for eg
Filesystem Mounted on
/dev/hda3 /data/db1 for DB1
/dev/hda4 /data/db2 for DB2

thanks in advance

Arvind S

"Many of lifes failure are people who did not realize how close they were to
success when they gave up."
-Thomas Edison