Jira Plugin Migration Jira 9.12 -> Jira 10

Hi.

U currently try to migrate an jira plugin from 9.12 to 10.3. Although i almost comment out the whole atlassian-plugin.xml I get following error :

Error creating bean with name ‘componentImportBeanFactoryPostProcessor’: Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.CannotLoadBeanClassException: Error loading class [at.generali.app.all.customfieldtype.MainSolutionVersionField] for bean with name ‘mainSolutionVersionField’: problem with class file or dependent class; nested exception is java.lang.NoClassDefFoundError: at.generali.app.all.customfieldtype.MainSolutionVersionField not found from bundle [Generali IT Plugin (at.generali.gatgit-jira-plugin)]
Error loading class [at.generali.app.all.customfieldtype.MainSolutionVersionField] for bean with name ‘mainSolutionVersionField’: problem with class file or dependent class; nested exception is java.lang.NoClassDefFoundError: at.generali.app.all.customfieldtype.MainSolutionVersionField not found from bundle [Generali IT Plugin (at.generali.gatgit-jira-plugin)]
at.generali.app.all.customfieldtype.MainSolutionVersionField not found from bundle [Generali IT Plugin (at.generali.gatgit-jira-plugin)]
com/atlassian/jira/issue/customfields/impl/GenericTextCFType
com.atlassian.jira.issue.customfields.impl.GenericTextCFType not found by at.generali.gatgit-jira-plugin [9]

The plugin ceates a couple of customFields which extends from GenericTextCFType

   <Import-Package>
                            com.atlassian.jira.web.action,
                            org.springframework.osgi.*;resolution:="optional",
                            org.eclipse.gemini.blueprint.*;resolution:="optional,
                            net.java.ao.*;resolution:="optional",
                            com.atlassian.activeobjects.external,

                            <!-- at.generali.app.*;resolution:="optional",-->

                            com.atlassian.jira.*;resolution:="optional",
                            com.atlassian.jira.config.*;resolution:="optional",

                            com.atlassian.jira.issue.customfields.impl,
                            com.atlassian.jira.issue.*;resolution:="optional",
                            com.atlassian.jira.issue.customfields.*;resolution:="optional",
                            com.atlassian.jira.issue.fields.*;resolution:="optional",
                            com.atlassian.jira.component.*;resolution:="optional",
                            com.atlassian.jira.user.*;resolution:="optional",
                            com.atlassian.jira.util.*;resolution:="optional",
                            com.atlassian.jira.workflow.*;resolution:="optional",

As u can see i added the package (com.atlassian.jira.issue.customfields.impl) to the import-package deklaration, but nevertheless it does not work.

Is this not exported anymore ? What is the issue here ? Should i extend from a different place (although marked PublicSpi ?)

Help very appreciated!

Thanks,

Reinhard Wagner (Customer!)