As it took me more time to figure this out than I wanted to invest into it (i.e. more than five minutes), I figured I would spare other people the trouble and put this online.
Follow this link for a Max patcher and Arduino code for sending serial data from Arduino to Max: https://sites.google.com/site/fkeel1/SerialMaxArduino.zip?attredirects=0&d=1
some more ramblings and random bits of information can be found here: http://fkeel.blogspot.com/2011/02/arduino-maxmspjitter-serial.html
a project I did using this code can be found here: http://fkeel.blogspot.com/2011/01/maybe-max-isnt-as-terrible-as-i-first.html