Sonar project sub-modules

Is it possible to define sub-modules on a module in the sonar-project.properties?

My current config looks like this:

sonar.projectKey=project
sonar.projectName=project
sonar.projectVersion=1.0

sonar.branch=master
sonar.sources=.
sonar.language=php

# Available modules
sonar.modules=module1, module2

# Global source directory
sonar.sources=.
sonar.language=php

# Module1
module1.sonar.projectName=Module1
module1.sonar.projectBaseDir=path/module1

# Module2
module2.sonar.projectName=Module2
module2.sonar.projectBaseDir=path/module2

But the module1 has also sub-modules.