10:36 AM EST - Penn West Energy Trust : said on Tuesday it will buy Vault Energy Trust for about $380 million to boost its oil and gas production. Penn West said each Vault Energy Trust unit will be exchanged for 0.14 of a Penn West Trust unit. Based on the Monday close for both securities, the offer is worth $4.25 per Vault Energy unit, a 9 percent premium. Penn West Energy Trust
units T.PWT.UN are trading up 46 cents at $30.84.
