Server :: After Reboot Tomcat 5 Will Not Start On RHEL3

We have three production websites running on RHEL 3 AS running tomcat 5. After a reboot last night Tomcat will not start and has the following in the catalina.out log:

Mar 20, 2011 4:09:31 PM org.apache.commons.digester.Digester startElement
SEVERE: Begin event threw error
java.lang.NoClassDefFoundError: org/apache/naming/resources/ProxyDirContext
at java.lang.Class.getDeclaredConstructors0(Native Method)
at java.lang.Class.privateGetDeclaredConstructors(Class.java:2389)
at java.lang.Class.getConstructor0(Class.java:2699)
at java.lang.Class.newInstance0(Class.java:326)
at java.lang.Class.newInstance(Class.java:308) .....

I have spoken with our Java Developers and they seem to think it is something up between httpd and tomcat at an OS level. Since Tomcat is not starting and giving an error that it is all ready running, I think you have a stale lock file. Look for the file /var/run/tomcat5.pid and cat or less it to see what the PID number is. If it matches the error, then delete the file and try to start Tomcat again. It should start this time.

Most common problem with Tomcat5. Try following :
1) Search PID in /tmp, if found delete it or else stop your tomcat.
2) Undeploy your application
3) Check out this link [URL] to know what causing tomcat to generate this error.

If none of them work then check your application configuration settings. [URL]. When I do start tomcat it appears to start:

[root@RPSI-2 san00]# service tomcat5 start
Starting tomcat5: Using CATALINA_BASE: /usr/share/tomcat5
Using CATALINA_HOME: /usr/share/tomcat5
Using CATALINA_TMPDIR: /usr/share/tomcat5/temp
Using JAVA_HOME: /usr/java/jdk1.6.0
[root@RPSI-2 san00]#

But then I try to find if it is running via ps -ef | grep tomcat5, I only receive my query. I perform the same query on Java and it also only returns my query.