tomcat error after upgrade

[Sam Kalamees]

Hi
A web app development required for tomcat to be upgraded from 6.0.20 to Tomcat 7.any. The app is not developed by me so no details.
When switching to tomcat 7.0.54 the webui returns error 500 and catalina.out outputs:

[2015-03-09 14:44:14,154] ERROR log4jFactory -8080-exec-5 - Unable to compile class for JSP
org.apache.jasper.JasperException: Unable to compile class for JSP
Caused by: java.lang.IllegalArgumentException: Page directive: invalid value for import

What could these errors hint?
Switching back to tomcat6 everything works. Also the same webapp strangely works with tomcat 7 on another server.
Thank you in advance!

[Bear Bibeault]

Sam Kalamees wrote:[2015-03-09 14:44:14,154] ERROR log4jFactory -8080-exec-5 - Unable to compile class for JSP
org.apache.jasper.JasperException: Unable to compile class for JSP
Caused by: java.lang.IllegalArgumentException: Page directive: invalid value for import

This intimates two things:

Scriptlets are being used in JSPs despite being 14 years obsolete.

An imported class is not being found.

To me, step 1 would be to determine which JSP is failing.