Web UI Error immediately upon login

Hi,

I am stuck at a point with RT (4.4.1). When I login, I get this error: An
internal RT error has occurred. Your administrator can find more details in
RT’s log files.

My rt.log has the following:

[90276] [Sat Nov 26 12:18:54 2016] [info]: Successful login for root from
105.58.149.231 (/opt/rt4/sbin/…/lib/RT/Interface/Web.pm:831)
[90276] [Sat Nov 26 12:18:54 2016] [error]: encountered object ‘1’, but
neither allow_blessed, convert_blessed nor allow_tags settings are enabled
(or TO_JSON/FREEZE method missing) at
/usr/local/lib/perl5/site_perl/JSON.pm line 154, line 25.

Stack:
[/usr/local/lib/perl5/site_perl/JSON.pm:154]
[/opt/rt4/sbin/…/lib/RT/Interface/Web.pm:193]
[/opt/rt4/sbin/…/lib/RT/Interface/Web.pm:4396]
[/opt/rt4/share/html/Elements/JavascriptConfig:87]
[/opt/rt4/share/html/Elements/Header:64]
[/opt/rt4/share/html/index.html:4]
[/opt/rt4/sbin/…/lib/RT/Interface/Web.pm:696]
[/opt/rt4/sbin/…/lib/RT/Interface/Web.pm:375]
[/opt/rt4/share/html/autohandler:53]
(/opt/rt4/sbin/…/lib/RT/Interface/Web/Handler.pm:208)
[90276] [Sat Nov 26 12:18:54 2016] [error]: encountered object ‘1’, but
neither allow_blessed, convert_blessed nor allow_tags settings are enabled
(or TO_JSON/FREEZE method missing) at
/usr/local/lib/perl5/site_perl/JSON.pm line 154, line 43.

Any ideas how I can fix the problem will be appreciated.

Best regards,
Odhiambo WASHINGTON,
Nairobi,KE
+254 7 3200 0004/+254 7 2274 3223
"Oh, the cruft."