By Alexei Oreskovic SAN FRANCISCO (Reuters) – Yahoo Inc delivered modest revenue growth in the first quarter but its shares jumped on strong results from Alibaba Group Holding Ltd ahead of the Chinese e-commerce companys highly anticipated initial public offering. Shares of Yahoo were up roughly 8 percent to $36.90 in afterhours trading on Tuesday. Yahoo said its revenue, excluding fees paid to partner websites, was $1.087 billion in the first quarter, up from $1.074 billion in the year-ago period. Analysts polled by Thomson Reuters I/B/E/S had expected adjusted revenue of $1.077 billion.