Using the -I flag in Linux

[PaperPilot]

Hi all:

I am compiling a D language program in two files and getting an ld error.

The files are: hello.d which has the main() routine.
Word.d has a class which is instantiated in hello

If I compile both files together like:

dmd hello Word

the program compiles and links successfully. If I compile Word.d first and then hello.d and include the working directory like:

dmd hello -I~/sandbox where sandbox is the working directory I get linker errors like: undefined reference to '_D4Word12__ModuleInfoZ'

D uses the gcc linker, ld, and I installed gcc 4.1.2 to get it. Is there another package I need to install?

Thanks in advance.