Thanks for the links.
The Sparkfun BMP085 breakout board has 4k7 pull-up resistors.
The K30 seems to have 56k pull-up resistors, or they recommend 56k, but I'm not sure of that.
So you are good, you don't have to add extra resistors.
The Sparkfun BMP085 board should have 3.3V.
The K30 needs 3.3V for "DVCC" and 5V for the "Supply Voltage" (I don't understand that), but the logic levels should be maximum 3.3V.
If you connect both sensors to the I2C-bus, the pull-up resistors of the BMP085 board will keep the I2C-lines between 0 and 3.3V (or a little more). So you have to connect both sensors to the I2C-bus at all times !
Some information about the I2C levels can be found here: http://arduino.cc/playground/Main/I2CBi-directionalLevelShifter
...while I was typing this, Graynomad had already answered it (and we came up with the same result).