Interfacing SD cards and DS1307 RTC clock

I have compiled header files and *.cpp files as libraries for reading DS1307 and reading/writing to/from SD cards. Both work fine seperatly. When I include both sets of header files the communicating with the SD card fails immedatly, as does (I think ) the serial comms to the PC.

I can 'fix' the problem by removing the DS1307.h file but then I loose this functionality.

Any suggestions for where I should start to look for potential problems/conflicts?

What is the best way to make the source code and header files available on the Forum?

Thanks, Col.