The setting to use the Security Realm "Collabnet Teamforge" is broken. 

I have installed Jenkins 2.277.3 fresh from WAR. At startup I have chosen to install the default advised plugins. After that:

1. created an initial user.
2. Installed the CollabNet plugin v2.0.7
3. Installed the Role-based Authorization Strategy v3.1.1
4. restarted Jenkins
5. set the Authentication to 'Role-Based Strategy'
6. in the "Manage and Assign Roles" created a new user with an ID that is available in Collabnet, and assigned the 'admin' role.
7. in the 'Configure Global Security' set the 'Security Realm' to the "Collabnet Security Realm" and filled in the link to our server.

When pressing "Apply" I get a popup saying "A problem occurred while processing the request" with some logging ID.

In the logging I see a.o.:

2021-04-29 06:28:07.253+0000 [id=25] INFO hudson.WebAppMain$3#run: Jenkins is fully up and running
2021-04-29 06:35:35.489+0000 [id=80] WARNING o.e.j.s.h.ContextHandler$Context#log: Error while serving http://localhost:9090/configureSecurity/configure
java.lang.ClassNotFoundException: hudson.util.spring.BeanBuilder
at jenkins.util.AntClassLoader.findClassInComponents(AntClassLoader.java:1387)
at jenkins.util.AntClassLoader.findClass(AntClassLoader.java:1342)
at jenkins.util.AntClassLoader.loadClass(AntClassLoader.java:1089)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
Caused: java.lang.NoClassDefFoundError: hudson/util/spring/BeanBuilder
at hudson.plugins.collabnet.auth.CollabNetSecurityRealm.createFilter(CollabNetSecurityRealm.java:101)
at hudson.security.HudsonFilter.reset(HudsonFilter.java:141)
at jenkins.model.Jenkins.setSecurityRealm(Jenkins.java:2629)
at hudson.security.GlobalSecurityConfiguration.configure(GlobalSecurityConfiguration.java:123)
at hudson.security.GlobalSecurityConfiguration.doConfigure(GlobalSecurityConfiguration.java:108)
at java.base/java.lang.invoke.MethodHandle.invokeWithArguments(MethodHandle.java:710)
at org.kohsuke.stapler.Function$MethodFunction.invoke(Function.java:396)

(complete log attached).

I have successfully used the feature with earlier versions :

    Jenkins (2.204.5), Collabnet 2.06, Role-based Auth. 2.16

One other thing that changed from earlier is that in the previous setup we used Oracle Java (jdk1.8.0_141_x86) . Now using OpenJDK (openjdk-11.0.2).

Anyone an idea ?