As has been mentioned before, SirCam tries to invade your system by disguising itself as a friendly file. It invades a friends address book and sends a message to all those in that book that reads something to the effect of,

I am writing for your advice on the attached file or something similar. The attached file will often appear legit in that it might relate to the friend from whom you received it. The virus takes a random file from their computer, attaches itself and sends it to you. The file varies in that the original file could be a .xls or Exel file or .doc a Word file or countless others. The clue that it is suspect is that the attached file will have more than one extension. for example if it invaded a fellow chippers computer you might get a file that was titled, chiplist.xls.bat . If your friend is an attorney it could be something like motioncontinue.doc.lnk . As you can see, while not always the case, you could be fooled in that the file might at quick glance fit the person from whom it came. You need to be vigilant to the double extensions. According to Norton's website, the second extension could be as follows. "The attachment is a file taken from the sender's computer and will have the extension .bat, .com, .lnk or .pif added to it.". The message might read, "I send you this file in order to have your advice
I hope you can help me with this file that I send
I hope you like the file that I sendo you
This is the file with the information that you ask for". If you have friends or clients that send you email in spanish Norton gives some translations for the common messages in spanish. Check http://www.symantec.com/avcenter/venc/data/w32.sircam.worm@mm.html for more information.