"Hey, can you please take a look at this bug?"
"I was wondering about this. Can we look?"
"Okay, we think we need a build with gprof enabled."
"We're happy to take a peek at the upgrader, but we're going to need a build."
"Bug 12345 is killing us. Any way we can put it near the top of the queue?"
Asking for things is a fact of life in a highly collaborative environment. I get asked for things quite often, too, and that's okay. Simply asking, though, isn't enough to get it done. As the asker, the onus is on me to make it easy for the person to do whatever I'm asking.
There are two pieces of information give you a much higher chance of actually getting a response to your request: (1) what you want, and (2) why you want it.
Describe not only the problem but also what you want done about it. Simply saying, "This is a problem." leaves ambiguity. The person you're asking for something may not do anything (after all, you haven't actually asked for some action), or may do something you don't expect.
Describe why you want this thing. This helps the other person invest in the issue. It matters more if the answer to "why am I doing this?" is apparent to the person who will actually do some work. It's really about respect, in this case; you're telling the other person that you understand the value of their time and understand that you need to justify (i.e., tell them why) this is worth spending their time on.
So feel free to ask for something. Feel free to be asked for something. Just make sure you let people know what you want and why, and it won't get pushed to the bottom of the person's queue.