This error means that the non-heap memory limit of the JVM has been reached. The non-heap memory is used to store class descriptions, so this error may appear when running huge applications.
To avoid it, you must increase the non-heap memory limit by adding -XX:MaxPermSize=256m Java option to the command line:
iscrun -J-XX:MaxPermSize=256m PROGNAME
java -XX:MaxPermSize=256m PROGNAME
256 means 256 MB and it specifies the maximum amount of non-heap memory that the JVM can allocate. If it’s not enough, try with higher values.