[Koha] Opac Template: Fatal Error in Loop Output

[Bo Schafers]

Hi Folks,

a) User wants to log into opac for user features (opac-user.pl)
b) The user has items on loan
c) User gets a server error page

Note: there is no error when there user has nothing on loan

Below is the respective error message from opac-error.log

HTML::Template->output() : fatal error in loop output : 
HTML::Template::param() : attempt to set parameter 'reserves' with an 
array ref - parameter is not a TMPL_LOOP! at 
/usr/local/share/perl/5.8.7/HTML/Template.pm line 3069, referer: 
http://opac.bswa.org/cgi-bin/koha/opac-user.pl

I'm not clued in enough to understand why this error occurs or how to 
interpret the log message. The logins just used to work and now suddenly 
they don't, This error is certainly not replicatable in the Liblime 
demo, so it's something to do with my setup.

Please, can anyone help  with suggestions?

TIA,
Bo