[CentOS] autofs and LDAP automount maps

Hi,

We've been using autofs and LDAP automount maps for years now, and it has worked well. We run an environment that has CentOS, RHEL, Solaris and FreeBSD servers and clients.

Historically, all our automount maps have looked like this:

-vers=3 server:/export/home/&

However, we're switching to NFSv4 and therefore we need to remove the -vers=3 flag. For CentOS 6.3, Solaris and FreeBSD clients, this causes them to mount with NFSv4, which is their default. However, the CentOS 5.x boxes are still defaulting to NFSv3 instead.

Looking in /etc/sysconfig/autofs, I see a setting for "OPTIONS", but I'm not sure if those are mount options or what.

Is there any way to cause CentOS 5.x to default to NFSv4 when using autofs?