[CentOS] Odd failure of smbd to start from init.d - CentOS 5.4

More data:

"service smb restart" - does NOT get smbd running (although shows "OK")

"sh /etc/init.d/smb restart" - DOES get smbd running

The "service" man page claims the only environment variables it passes are
LANG and TERM. But that can't be the key, since 

"/etc/init.d/smb restart" - does NOT get smbd running (although shows "OK")

For that matter

"bash /etc/init.d/smb restart" - DOES get smbd running

Changing the first line of init.d/smb to /bin/bash from /bin/sh changes all
this not at all.

What the heck can this be?

Whit