modulepath with multiple modules and inability to install more than one module using jmod

[Sahoo]

I have the following source layout:
./src/m1-1.0/m1/p1/Foo.java
./src/m1-1.0/m1/p2/Bar.java
./src/m1-1.0/module-info.java
./src/m2-1.0/module-info.java

I have followed the recommendation of encoding version number in source 
directory name as mentioned in the modulepath/javac pdf, although I am 
convinced about it and hence have a separate email about it.

This is how I invoke javac:

javac -d modules/ -modulepath src/:modules/ `find src/ -name "*.java"`

I am slightly confused as to whether I should use -modulepath src/ or
-modulepath modules/ or -modulepath src/:modules/. I guess what I have
used covers the case where module/ already contains some compiled
modules that are required by the current compilation. Someone can help me
understand this better.

This generates classes like this:
./modules/m1-1.0/m1/p1/Foo.class
./modules/m1-1.0/m1/p2/Bar.class
./modules/m1-1.0/module-info.class
./modules/m2-1.0/module-info.class

Because the classes are generated under modules/m1-1.0 and
modules/m2-1.0 instead of modules/, I can't add more than one module at
a time. e.g., I can't do:

jmod -L mlib install modules/ m1 m2

This fails with:
I/O error: modules/m1/module-info.class (No such file or directory)

I have to do:
jmod -L mlib install modules/m1-1.0 m1
jmod -L mlib install modules/m2-1.0 m2

It's a bit inconvenient as you can see.

Thanks,
Sahoo