Issues with Openldap upgrade 2.4.21 to 2.4.31

[Laurent Dumont <ml@coldnorthadmin.com>]

Hi gents,

I'm currently trying to upgrade my "aging" Ubuntu 10.04 physical server 
with OpenLdap 2.4.21 to a brand new VM running 2.4.31 (which seems to be 
provided by default with the standard repository while being somewhat 
old?). That said, I'm running into a few issues.

Am I correct in assuming that a standard migration would go something 
like this :

#On the original LDAP server
sudo slapcat -l /root/ldapdump

#Copy that file over to the new LDAP server
sudo slapadd -v -d 1 -l ldapdump

Unfortunately, that's where it fails. I see :

560ade84 str2entry: invalid value for attributeType objectClass #2 
(syntax 1.3.6.1.4.1.1466.115.121.1.38)
slapadd: could not parse entry (line=1)

It seems that I'm missing something pretty obvious here. Anyone has any 
pointers?

Thanks