Katy Perry isn’t singing a very sweet tune these days. In fact, she’s told Australian fashion designer Katie Perry to cease and desist using her same name (different spelling) to promote her loungewear, reports MTV.

According to the article, Katie Perry has been designing and selling clothing under her name for the past two years, and after opening a storefront, filed paperwork to trademark her name for the store and her line.

But surprise! Shortly after filing, she received a request to stop using her own name — the name she was given at birth — from an Australian law firm representing singer Katy Perry. If Katie doesn’t back down, a lawsuit will follow, and a judge will decide which Perry prevails.

This potential trademark lawsuit might rival the one that stylist Rachel Zoe threatened Christopher Suave with earlier this year…

Sauve whipped up T-shirts stating “Bananas,” (in an homage to the stylist) but Zoe had the cease-and-desist letter in Suave’s hands faster than he could say “silkscreen.”

Apparently, she trademarked the word “bananas.” For real? That’s B-A-N-A-N-A-S! Maybe Gwen Stefani should send a C&D to Zoe…

Designer Katie Perry was quoted in the MTV article saying,

“I got such a huge shock. It really felt like I was being intimidated and bullied into signing everything away. It asked me to give up the trademark, withdraw sales of my clothes, withdraw any advertising and any Web sites and sign that I will not in the future use a similar trademark to Katy Perry. I pretty much burst into tears.”

Okay, so we could see Katy taking issue if Katie were a musician. But she’s not.