Hallmark.com, the Web site of Kansas City, Mo., card maker Hallmark, appeared to be having a rough Valentine's Day yesterday.

Midafternoon, visitors trying to send or receive electronic cards saw a message telling them the site was temporarily off-line for maintenance. Later the company's message changed to say, "Valentine's Day is keeping us extra busy and that means our store is full right now. Please try back in a little while."

AlertSite, a Florida company that monitors Web site performance, reported no problems accessing the Hallmark site from midnight on until about 7 a.m.; at that point, its servers got through only 29 percent of the time. Performance picked up at various points in the day with the servers having the most problems getting through from noon to 1 p.m.

AlertSite reported few problems at other popular Valentine sites, such as BlueMountain.com, VictoriasSecret.com and ProFlowers.com.

Hallmark sells flowers and gifts through its Web site in addition to offering hundreds of free electronic greeting cards. Though Christmas is a bigger e-card holiday overall, Valentine's Day has, in the past, been the site's busiest single day. In 2003, the company reported 2.6 million visits on that day alone.