I`ve found that some people now using a different way to fool google`s page rank rating system.No redirection or header modification used on the page.They only put their high pr websites index on ow pr ranked website.This way they get a very high pr in next pr update.
Why not work for it instead of taking the easy way out. After working hard on creating a website, why should you waste time at all looking for ways and means to do things wrong, and if something really goes wrong, the end result is wasted effort.
I shall say that it is not wrong to link your Low PR sites with high PR site (if someone has). It is obvious that you have already invest a lot of time and money in your high PR site so there is nothing wrong if you are linking your sites to get some high PR.