How to enable multiple landmarks correctly?

I wanted to enable lanmarks enabled for multiple weightings.
I changed the config.properties to this:

prepare.lm.weightings=straight,fastest_traffic

it creates lanmark for both of the weightings.
but the problem is that it uses one of the landmarks. and the speed of one of the weighting increases. but also the other gets slow.

how I could do this correctly? to enable landmarks for each of the weightings?