[rules-users] Need Help: Errors while running FibonacciExample

Hi, After successfully compiling the example code FibnacciExample.java, I tried to run it, I get the following error, let me know how to solve it: java FibonacciExample Exception in thread "main" java.lang.ExceptionInInitializerError at java.lang.Class.initializeClass() (/usr/lib/libgcj.so.6.0.0) at org.drools.semantics.java.RuleBuilder.<clinit>() (Unknown Source) at java.lang.Class.initializeClass() (/usr/lib/libgcj.so.6.0.0) at org.drools.compiler.PackageBuilder.addRule(org.drools.lang.descr.RuleDescr) (Unknown Source) at org.drools.compiler.PackageBuilder.addPackage(org.drools.lang.descr.PackageDescr) (Unknown Source) at org.drools.compiler.PackageBuilder.addPackageFromDrl(java.io.Reader) (Unknown Source) at FibonacciExample.main(java.lang.String[]) (Unknown Source) at gnu.java.lang.MainThread.call_main() (/usr/lib/libgcj.so.6.0.0) at gnu.java.lang.MainThread.run() (/usr/lib/libgcj.so.6.0.0) Caused by: java.util.regex.PatternSyntaxException: At position 2 in regular expression pattern: expected end of character class (.*)\bmodify\s*\(([^)]+)\)(.*) ^ at java.util.regex.Pattern.Pattern(java.lang.String, int) (/usr/lib/libgcj.so.6.0.0) at java.util.regex.Pattern.compile(java.lang.String, int) (/usr/lib/libgcj.so.6.0.0) at org.drools.semantics.java.KnowledgeHelperFixer.<clinit>() (Unknown Source) at java.lang.Class.initializeClass() (/usr/lib/libgcj.so.6.0.0) ...8 more Is it require to place .drl file in the same directory as that of the source code ? Thanks, Venkatesh The information contained in this electronic message and any attachments to this message are intended for the exclusive use of the addressee(s) and may contain proprietary, confidential or privileged information. If you are not the intended recipient, you should not disseminate, distribute or copy this e-mail. Please notify the sender immediately and destroy all copies of this message and any attachments. WARNING: Computer viruses can be transmitted via email. The recipient should check this email and any attachments for the presence of viruses. The company accepts no liability for any damage caused by any virus transmitted by this email. www.wipro.com