We are successfully running an application based on Spring 3.2.1.RELEASE and Spring Security 3.1.3.RELEASE. We didn't have any particular problem while setting this up.
Unfortunately I don't have any source that show this is officially supported.
If you are using Maven in your project, you should force versions to avoid having the same jars with multiple versions in your classpath:
<properties>
<spring.version>3.2.1.RELEASE</spring.version>
<spring-security.version>3.1.3.RELEASE</spring-security.version>
</properties>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.security</groupId>
<artifactId>spring-security-core</artifactId>
<version>${spring-security.version}</version>
</dependency>
<!-- Etc. (specify a fixed version for each Spring jar) -->
</dependencies>
</dependencyManagement>