nginx reload failing: `object version does not match bootstrap parameter`

I added a server stanza to my virtual.conf, and now nginx seems to have a problem reloading the config.

At this point I don't know what exactly is going wrong or how to debug better. Any help would be most appreciated.

The config test succeeds:

root@server:~# service nginx configtest
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful

I'm tailing the logfile. Upon reload, the following error is logged. As far as I can see, the new config is not used.

root@server:~# service nginx reload
Reloading nginx:                                           [  OK  ]
root@server:~# 
==> /var/log/nginx/error.log <==
nginx object version 0.8.54 does not match bootstrap parameter 1.0.15 at /usr/lib64/perl5/XSLoader.pm line 94.
Compilation failed in require.
BEGIN failed--compilation aborted.
2012/10/18 12:31:07 [alert] 9620#0: perl_parse() failed: 2

This is the version of nginx I'm running:

root@server:~# yum info nginx
Loaded plugins: fastestmirror, presto
Loading mirror speeds from cached hostfile
 * base: ftp.udc.es
 * epel: mirror.nl.leaseweb.net
 * extras: ftp.udc.es
 * updates: ftp.cica.es
Installed Packages
Name        : nginx
Arch        : x86_64
Version     : 1.0.15
Release     : 2.el6
[...]

Server OS: CentOS release 6.3 (Final)