ok,
here is a replacement for the _getResults method in Ldap.php.
It replaces the main-loop by an first_entry - next_entry loop.
The tricky part is how to tell, whether or not an attribute has to be 
retrieved
by ldap_get_values_len (is binary). This is done in 
_isBinaryValue($atrribute).
If schema-checking is available, the 'certificate' and 'jpeg' syntaxes 
are selected.
Otherwise an additional server configuration option is needed.
e.g. 'binary' => array('jpegPhoto','userCertificate;binary').

General support has been added to Turba, but not for the LDAP driver 
yet. A patch for LDAP would be nice.

I've modified the ldap.php driver from Turba 2.1.1 since I need to 
store binary encoded certificates in our directory. My version uses 
ldap_get_values_len() instead of ldap_get_entries() to fetch binary 
values. The attribute name "usercertificate;binary" is hard coded. 
Certificates are converted from and to Base64. Several places in the 
code are still marked with FIXME. The driver works for us. I am going 
to fix the remaining issues but currently I have to work on other 
things.

It would be nice if Turba could handle the display of binary objects.   
Immediate use, for instance, would be display of user pictures, such 
as a jpegPhoto attribute stored in LDAP, but other binary objects 
exist as well (crypto-related items, for instance).