ivy error building pentaho-platform-extension

i'm trying to build pentaho from source ( 5.0.1 ).
With the project pentaho-platform-extensions i get an error on ivy resolve :

Failed to configure Ivy for ivy.xml[*] in pentaho-platform-extensionsError while resolving the ivy instance for ivy.xml[*] in 'pentaho-platform-extensions':
Unrecognized variables in the Ivy settings file ${workspace_loc:pentaho-platform-extensions/ivysettings.xml}

i compared the ivysettings.xml file of pentaho-platform-extensions with that of the other project and teh content is the same .
The content of teh file is this :

<?xml version="1.0" encoding="UTF-8"?>
<ivysettings>
<properties environment="env" />
<property name="ivy.local.default.root" value="${ivy.default.ivy.user.dir}/local" override="true" />
<property name="ivy.local.default.artifact.pattern" value="[organisation]/[module]/[revision]/[type]s/[artifact]-[revision].[ext]"
override="false" />


<settings defaultResolver="pentaho-chained-resolver" />
<include url="${ivy.default.settings.dir}/ivysettings-public.xml" />
<include url="${ivy.default.settings.dir}/ivysettings-local.xml" />
<resolvers>
<chain name="pentaho-chained-resolver">
<resolver ref="local" />
<dual name="pentaho">
<url name="pentaho-ivy">
<ivy pattern="http://repo.pentaho.org/artifactory/repo/[organisation]/[module]/[revision]/[module]-[revision].ivy.xml" />
</url>
<ibiblio name="pentaho-mvn" m2compatible="true" root="http://repo.pentaho.org/artifactory/repo" />
</dual>
<resolver ref="public" />
<ibiblio name="java-net-maven2" root="http://download.java.net/maven/2/" m2compatible="true" />
</chain>
</resolvers>
<caches lockStrategy="artifact-lock" resolutionCacheDir="${ivy.default.ivy.user.dir}/resol-cache${env.EXECUTOR_NUMBER}" />
</ivysettings>



have you any idea about this error ?
thanks for any response .