Help please: persistent mealy bugs

I have a hedge of Lillypilly that has become encrusted with the soft, white bug. I think it is mealy bug.
I've tried Malathion spray without success.
Someone mentioned a spray made up of liquid detergent, cooking oil and water. However, I would appreciate your advice before I go ahead with another suggestion.
Many thanks...in anticipation
Anna

I've read about this recipe where you have to grate the rind of a lemon or an orange, mix it with half a liter of boiling water and leave it overnight. Then you'll have to strain the whole thing through a coffee filter to remove the bigger pieces. After that it says to put the mixture in a spray bottle and spray the plants with the bugs on them. It should work, I think.

I had these all over one of my hibiscus along with ants farming them. I have used a jet spray of water to dislodge them but you do have to do this repeatedly to really get rid of them (I'm against chemical warfare in my garden where possible). Good luck with ridding your lillypillys of them.
Wikipedia has some information that is useful. Isopropyl alchohol and detergent is one suggestion.

"Fickle Prickles" website has just posted a blog / solution to mealybug problems........worth a look.