The IR controller which comes with Dell Vostro is supported by Gnuk.
Its protocol is Phillips RC-6.
Here is the table of code and button.
code button 0x10 Speaker Loud 0x11 Speaker Quiet 0x0d Speaker Mute 0xce ▲ 0xcf ▼ 0x58 △ 0x5a ◁ 0x5c ✓ 0x59 ▽ 0x5b ▷ 0xa4 ⇦ 0x2f ◀◀ 0x2c ▶/Ⅱ 0x2e ▶▶ 0x21 |◀ 0x31 ■ 0x20 ▶|