A custom plugin for accounting was installed successfully, but after that provisioning of any services from the online store, manual provisioning from OBAS or reading the existing Invoices, Orders and so on, is not possible.
The following error is shown in the OBAS log (
[2015/05/26 20:22:21] [FATAL]  [Error::throw] URI handler (HSPC::Billing::Ar_doc->teaser_office) error: Can't call method "enum_group_id" on unblessed reference at /usr/local/share/perl5/HSPC/MT/BillingFactory.pm line 1114.
The issue was caused by the custom accounting plug-in.
Please contact Odin Technical Support for assistance.