my cat is urinating on my husband's clothes

    We have had our cat Polka Dot for about a year.  She belonged to my father in LA and lived with two other cats, whom she got along with pretty well.  When my Dad died Polka Dot came to live in NY with us and was an only-cat for about a year.  She is very affectionate and havs a nice disposition.  We love her so much. We wanted her to have company so four months ago we adopted a male from the shelter.  He has just turned two and his name is Felix.  He is very alert and playful and though he was very aftraid of everything at first, he has mellowed a lot and is turning into a mush! 

     They get along fairly well except for a few very bothersome things.  We have plenty of room and did all the right things, like keeping them apart at first, etc.  He was with other cats at the shelter and is very social.  He seemed to like Polka Dot and wants to play with her.  She on the other hand, didn't want much to do with him and showed syptoms of anxiety (hiding, withdrawing a little.)  Slowly she seemed to be letting her guard down and they began sniffing each other, touching noses, and eating next to each other.  We all sleep on the bed together.  However, they start playing and things appear finel and suddenly she is under her special chair and he is circling her. Then she starts crying (sometimes they are playing/fighting and sometimes he's just near her) We run in to break it up and squirt Felix with water.  Felix never shows any kind of aggression toward her except this rough playing and it's always in the same room. 

    In the past four months, Polka Dot has unrinated on my husband's clothing 4 times.  She never goes ont he rug or on furniture, it's always on my husband's shorts or shirts, which she finds on the floor or on a chair.  At first I didn't know it was her except the lack of smell  (female urine is much less powerful than male) and the circumstances pointed to Polka Dot.  Suddenly last night she urinated on his shirt right in front of us!  I was so upset.  I realize this is a marking her territory thing, but how do we stop it?  We show both cats tons of attention and love and do everything possible to make Polka Dot feel secure.  We are going to rennovate our house soon so the urine isn't worrying me as far as the house is concerned, since it's all getting ripped up.  We are just concerned about her well being and how to stop this behavior.  They are both well behaved cats and actually spend a lot of time hanging out in the same rooms peacefully.  What can we do??????