Zimbra Server Statistics does not show time interval

[nix]

When I look at the graphical statistics via the Zimbra Admin portal -> Server Statistics, the graphs look fine but the time interval is displayed as,

interval: %d minutes

directly below the graph. Does anyone else have %d here?

This has always been the case since I first installed ZCS 6.0.6. I do have a non-standard install, running ZCS on CentOS on a VPS.

[zimbra@mail ~]$ cat /etc/*release*
CentOS release 5.5 (Final)

[zimbra@mail ~]$ uname -a
Linux mail.domain.net 2.6.18-194.26.1.el5xen #1 SMP Tue Nov 9 13:35:30 EST 2010 x86_64 x86_64 x86_64 GNU/Linux

[zimbra@mail ~]$ zmcontrol -v
Release 6.0.10_GA_2692.RHEL5_64_20101215170845 CentOS5_64 FOSS edition.

I do remember pre ZCS install having to install prerequisites mentioned in the installation manual, as well as some basic utilities like: file, iostat, etc. FYI - without file, all mail would get stuck in one of the Mail Queues (the Deferred Queue from memory).

My VPS provider supplies a number of 'pre-packaged' distros, one of them being CentOS with Webmin pre-installed. One would think they would have included the file utility but obviously not - which made me think there may be more missing, hence not displaying the time interval properly - or the C library printf function...

Any ideas?