Installing and running Arduino 1.0

Currently I am using Arduino 022. I downloaded the 1.0 version and unzipped it. When I try to compile the Blink program it says "Blink.cpp:8:21: error: Arduino.h: No such file or directory". Can 1.00 and 22 co-exist? Any help will be appreciated. Thanks

If they're properly unzipped to different folders.

I unzipped it properly, and installed it properly. It gets the same message. Arduino.h is available in the Hardware folder. How do you fix this problem?

Found the problem. You have to change Preferences in the File tab to show the new folder.

JerryJonz: [..] to show the new folder.

What does that mean? Sketches folder? O_o

I think this is the easiest way to solve the problem:

To update old cores (such as Sanguino)

echo "#include \"WProgram.h\"" > hardware/Sanguino/cores/arduino/Arduino.h

To compile old programs on new cores (>=1.0)

echo "#include \"Arduino.h\"" > hardware/arduino/cores/arduino/WProgram.h