Timestamp or dependency problem with automake

[Steve Kreyer]

Hi,

I have some problems compiling my project with make.
My directory structur is as follows:
topsrcdir/src/
topsrcdir/src/regex
topsrcdir/src/tidy

When i call make for 2nd time in topsrcdir, make does compile the 
sources which
are located in src from scratch, even if they have not modified.
When i call make for 2nd time in topsrcdir/src everything went well
and make says: "nothing to be done..."

Can anyone figure out what is wrong? Do you need  additional informations?

Thanks in advance...

Steve