Summer brings out perhaps the worst fashion mistakes when it comes to dressing for work, and Hewlett-Packard has apparently just put the smackdown on T-shirts and shorts at the office.

The rumored memo, as reported by UK tech site the Register, asked some R&D employees within HP Enterprise Services to dress “smart casual” last week.

News of the mandate came to the Register via some HP employees. “If you aren’t dressed like the models in the posters that HP displays around its locations, then your appearance is sapping the productivity of the workers around you,” an anonymous source told the site.

The memo was reportedly sent out because HP management felt visiting customers might be “put off by scruffy-looking R&D engineers” around the offices.

Here’s what’s on the no-fly HP fashion list, according to the Register: “Men should avoid turning up to the office in T-shirts with no collars, faded or torn jeans, shorts, baseball caps and other headwear, sportswear, and sandals and other open shoes. Women are advised not to wear short skirts, faded or torn jeans, low-cut dresses, sandals, crazy high heels, and too much jewelry.”

Oregon Live posts this update for Pacific Northwest workers worried about wearing real clothes: “The dress code apparently applies only to workers in HP’s enterprise services group, the division that serves large, corporate clients.”

Would you fight for your right to wear mandals? Or are you on the side of leaving the weekend-warrior gear at home?