One month after warning that its sales pace was unsustainable, Starbucks' ( SBUX) monthly sales growth again topped 30%. The coffee chain posted $494 million for its five-week March period, the company announced on Wednesday. On a same-store basis, which compares the results of outlets open more than a year, the company's sales grew 12%. The results stand in contrast to a warning issued by company CEO Howard Schultz last month. In February, the company posted 32% total sales growth and 13% same-store sales growth. But Schultz warned investors to expect 20% overall sales growth and 3% to 7% growth in comparable-store sales over the longer term. For the first half of its fiscal year, Starbucks posted $2.5 billion in total revenue, which is up 29% from the same period last year. The company's same-store sales have grown 11% in the first six months of its current fiscal year. The sales announcement came after the close of regular trading on Wednesday. In after-hours trading, Starbucks' stock was recently up 24 cents, or 0.6%, to $38.11. The company's shares closed regular trading down 16 cents, or 0.4%, to $37.87.