database names are all numbers now

after i ran vacuum analyze, i see that all my database directories with
respect to their database names have changed to all numbers:

# ls -l /var/pgsql/data
total 17
-rw-------  1 pgsql  wheel     4 Dec 30 15:45 PG_VERSION
drwx------  6 pgsql  wheel   512 Jan  8 05:28 base
drwx------  2 pgsql  wheel   512 Jan  3 14:21 global
-rw-------  1 pgsql  wheel  7399 Dec 30 15:45 pg_hba.conf
-rw-------  1 pgsql  wheel  1118 Dec 30 15:45 pg_ident.conf
drwx------  2 pgsql  wheel   512 Jan  8 16:45 pg_xlog
-rw-------  1 pgsql  wheel   595 Jan  8 04:14 postgresql.conf
-rw-------  1 pgsql  wheel    93 Jan  8 10:22 postmaster.opts
-rw-------  1 pgsql  wheel    22 Jan  8 10:22 postmaster.pid
# ls -l /var/pgsql/data/base
total 8
drwx------  2 pgsql  wheel  1536 Dec 30 16:02 1
drwx------  2 pgsql  wheel  1536 Dec 30 15:45 18719
drwx------  2 pgsql  wheel  2048 Jan  8 16:31 397915
drwx------  2 pgsql  wheel  1536 Jan  8 05:28 9829118

is this normal?