Multi project release fails if site declared in pom.xml

I can do
mvn release:prepare
mvn release:perform

If i include
<site>
<id>site</id>
<name>My site server</name>
<url>scpexe://mysite.com/var/www/html</url>
</site>

in the parent pom I can do a
mvn release:prepare
but mvn release:perform fails

[INFO] [INFO] Reactor Summary:
[INFO] [INFO]
[INFO] [INFO] My parent .......................................... FAILURE [ 7.363 s]
[INFO] [INFO] common ............................................. SKIPPED
[INFO] [INFO] Web Application Project ............................ SKIPPED
[INFO] [INFO] ------------------------------------------------------------------------
[INFO] [INFO] BUILD FAILURE
[INFO] [INFO] ------------------------------------------------------------------------
[INFO] [INFO] Total time: 7.723 s
[INFO] [INFO] Finished at: 2015-10-13T11:06:32+02:00
[INFO] [INFO] Final Memory: 32M/393M
[INFO] [INFO] ------------------------------------------------------------------------
[INFO] [ERROR] Failed to execute goal org.apache.maven.plugins:maven-site-plugin:3.4:site (default-site) on project my-parent: failed to get report for org.apache.maven.plugins:maven-javadoc-plugin: Failed to execute goal on project my-webapp: Could not resolve dependencies for project example:my-webapp:war:1.0.9: Could not find artifact example:my-common:jar:1.0.9 in repo (https://myrepo.com/content/groups/public/)