Spring, 파일 업로드 예외

java.lang.NoSuchMethodError: org.apache.commons.io.output.ByteArrayOutputStream.writeTo(Ljava/io/OutputStream;)V
    at org.apache.commons.io.output.DeferredFileOutputStream.thresholdReached(DeferredFileOutputStream.java:182)
    at org.apache.commons.io.output.ThresholdingOutputStream.checkThreshold(ThresholdingOutputStream.java:226)
    at org.apache.commons.io.output.ThresholdingOutputStream.write(ThresholdingOutputStream.java:130)
    at org.apache.commons.fileupload.util.Streams.copy(Streams.java:103)
    at org.apache.commons.fileupload.util.Streams.copy(Streams.java:66)
    at org.apache.commons.fileupload.FileUploadBase.parseRequest(FileUploadBase.java:366)
    at org.apache.commons.fileupload.servlet.ServletFileUpload.parseRequest(ServletFileUpload.java:126)
    at org.springframework.web.multipart.commons.CommonsMultipartResolver.parseRequest(CommonsMultipartResolver.java:155)
    at org.springframework.web.multipart.commons.CommonsMultipartResolver.resolveMultipart(CommonsMultipartResolver.java:138)
    at org.springframework.web.servlet.DispatcherServlet.checkMultipart(DispatcherServlet.java:887)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:750)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:669)
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:585)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:144)
    at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:237)
    at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:167)

---

동일한 라이브러리가 lib에도 있고, lib에 있는 .jar 안에 또 있는데 상호 버전이 다른 상태에서 .jar에 있는게 classpath에 먼저 걸린경우..