Spring Major version '3' expected, but you are running with version: 4.0.5.RELEASE

I recently upgraded to spring-core 4.0.5 and made sure all other Spring components are in compatible versions. The only things that I didn't upgrade were spring-ldap-1.3.1 and spring-security-3.1.2.

After I deployed the WAR to the Tomcat server, I saw some message on the Tomcat console that reads "Spring Major version '3' expected, but you are running with version: 4.0.5.RELEASE. Please check your classpath for unwanted jar files.". But there was no exception or anything, the server started up successfully and application seemed to work just fine.

Listening for transport dt_socket at address: 8889
Mar 26, 2015 6:08:39 PM org.apache.catalina.core.AprLifecycleListener init
INFO: Loaded APR based Apache Tomcat Native library 1.1.32 using APR version 1.5.1.
Mar 26, 2015 6:08:39 PM org.apache.catalina.core.AprLifecycleListener init
INFO: APR capabilities: IPv6 [true], sendfile [true], accept filters false], random [true].
Mar 26, 2015 6:08:40 PM org.apache.catalina.core.AprLifecycleListener initializeSSL
INFO: OpenSSL successfully initialized with version OpenSSL 1.0.1j 15 Oct 2014
Mar 26, 2015 6:08:40 PM org.apache.coyote.http11.Http11AprProtocol init
INFO: Initializing Coyote HTTP/1.1 on http-8888
Mar 26, 2015 6:08:40 PM org.apache.coyote.ajp.AjpAprProtocol init
INFO: Initializing Coyote AJP/1.3 on ajp-8009
Mar 26, 2015 6:08:40 PM org.apache.catalina.startup.Catalina load
INFO: Initialization processed in 1142 ms
Mar 26, 2015 6:08:40 PM org.apache.catalina.core.StandardService start
INFO: Starting service Catalina
Mar 26, 2015 6:08:40 PM org.apache.catalina.core.StandardEngine start
INFO: Starting Servlet Engine: Apache Tomcat/6.0.43
Mar 26, 2015 6:08:40 PM org.apache.catalina.startup.HostConfig deployDescriptor
INFO: Deploying configuration descriptor host-manager.xml
Mar 26, 2015 6:08:41 PM org.apache.catalina.startup.HostConfig deployDescriptor
INFO: Deploying configuration descriptor manager.xml
Mar 26, 2015 6:08:41 PM org.apache.catalina.startup.HostConfig deployWAR
INFO: Deploying web application archive my-application-ui.war
log4j:WARN No appenders could be found for logger (org.springframework.web.context.ContextLoader).
log4j:WARN Please initialize the log4j system properly.
Mar 26, 2015 6:08:42 PM org.apache.catalina.startup.HostConfig deployWAR
INFO: Deploying web application archive my-application-web-service.war
**-*** Spring Major version '3' expected, but you are running with version: 4.0.5.RELEASE. Please check your classpath for unwanted jar files.**
-Root WebApplicationContext: initialization completed in 39254 ms

I went to WEB-INF\lib and saw the Spring jars as follows.

spring-aop-4.0.5.RELEASE.jar
spring-beans-4.0.5.RELEASE.jar
spring-context-4.0.5.RELEASE.jar
spring-context-support-4.0.5.RELEASE.jar
spring-core-4.0.5.RELEASE.jar
spring-expression-4.0.5.RELEASE.jar
spring-jdbc-4.0.5.RELEASE.jar
spring-jms-4.0.5.RELEASE.jar
spring-orm-4.0.5.RELEASE.jar
spring-oxm-4.0.5.RELEASE.jar
spring-tx-4.0.5.RELEASE.jar
spring-web-4.0.5.RELEASE.jar
spring-webmvc-4.0.5.RELEASE.jar
spring-ws-core-2.2.0.RELEASE.jar
spring-ws-security-2.2.0.RELEASE.jar
spring-ws-support-2.2.0.RELEASE.jar
spring-xml-2.2.0.RELEASE.jar
spring-ldap-1.3.1.RELEASE-all.jar
spring-ldap-core-1.3.1.RELEASE.jar
spring-security-config-3.1.2.RELEASE.jar
spring-security-core-3.1.2.RELEASE.jar
spring-security-ldap-3.1.2.RELEASE.jar
spring-security-web-3.1.2.RELEASE.jar

I couldn't figure out where this message comes from and for what reasons. Any help is greatly appreciated.