UPDATE: package/class imports in reports fail after upgrade 6.3.0 -> 6.3.1

[m00hk00h]

Hey there!

I have an application that compiles a lot of reports as build time and fills them at user requests during runtime.
I use the library version of jasperreports as dependency through Maven and just increased the version number. I was prepared for API changes and different behaviour with the new version. However there is one thing I just can't seem to work out...

I use a utility package in some "text field"-elements in report designs that use static methods for stuff like formatting or validation. The package is in the same project and after compiling in the same .jar-file as the reports. Example:

<textFieldExpression><![CDATA[TemplateUtils.formatIban($P{iban})]]></textFieldExpression>

The problem is that this package or even the classes in my own packages are no longer recognized when trying to compile reports:
"de.company.app.utils cannot be resolved"
These packages are definitely on classpath of the project. Also, external libraries referenced as Maven dependencies (like Apache commons) are recognized without trouble. Only my own packages in the project are affected.

Even when trying to compile directly through the Eclipse plugin or a fresh installation of Jaspersoft Studio 6.4.3 compiling fails with the same error.
I've gone through the changelog and didn't find anything relating to this.

Please help! Thanks in Advance!
 

UPDATE:
The weird behaviour starts kicking in with Version 6.3.1.
6.3.0 works flawlessly!