Error appears when creating Advanced Workflow with long description

Steps to reproduce:
1. Start creation of Advanced Workflow (Adhoc or Review and Approve);
2. In Description field enter any text (approximately 300 symbols);
3. Choose any reviewer and click Finish button; -> System error message appears:

Please correct the errors below then click Finish.

• A system error happened during the operation: Hibernate operation: could not insert: [org.jbpm.context.exe.variableinstance.StringInstance]; uncategorized SQLException for SQL [insert into JBPM_VARIABLEINSTANCE (VERSION_, NAME_, CONVERTER_, TOKEN_, TOKENVARIABLEMAP_, PROCESSINSTANCE_, STRINGVALUE_, CLASS_) values (?, ?, ?, ?, ?, ?, ?, 'S')]; SQL state [01004]; error code [0]; Data truncation: Data too long for column 'STRINGVALUE_' at row 1; nested exception is com.mysql.jdbc.MysqlDataTruncation: Data truncation: Data too long for column 'STRINGVALUE_' at row 1

Expected result:
Description field should have appropriate length limit or more friendly notification should inform the user;
LubaPa