08 is part of the Emergency number for several countries and is treated just like 911 when dialed from a cell phone. Even if the keypad is locked, dialing 08, 911, 112 and other internationally recognized Emergency numbers.
You can read more about it and the number combinations that will still dial out on any GSM brand of cell phones with or without the keypad locked.
This may not be true for Domestic GSM phones (i.e. those with only the 850/1900Mhz bands) that they will recognize the other international emergency numbers.
This seems to be true for US CDMA phones to only dial 911 since it will only work (by default) in the US/Canada.