[xwiki-users] Column20Macro error

Hi, I downloaded the Column20Macro jar and put it in my WEB-INF/lib directory. Then, after restarting my server, I tried to use it to display two basic columns but I had this error : Failed to execute section macro : org.xwiki.rendering.macro.MacroExecutionException: Section macro expect at least one column macro as first-level children at org.xwiki.rendering.internal.macro.column.SectionMacro.execute(SectionMacro.java:78) at org.xwiki.rendering.internal.macro.column.SectionMacro.execute(SectionMacro.java:25) at org.xwiki.rendering.internal.transformation.MacroTransformation.transformOnce(MacroTransformation.java:174) at org.xwiki.rendering.internal.transformation.MacroTransformation.transform(MacroTransformation.java:119) at org.xwiki.rendering.internal.transformation.DefaultTransformationManager.performTransformations(DefaultTransformationManager.java:72) [...] at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:409) at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582) It's quite weird because I used two column macro. Here my code : {{section justify="true"}} {{column}} a {{/column}} {{column}} b {{/column}} {{/section}} When I wrote use only one column macro inside the section one, I didn't have that error... But until two columns macro, the error appeared... Did I miss something ? Thanks, Marine