Farmin to Jacala, WA

Roc Oil Company Limited
11 May 2005






11 May 2005


                         ROC OIL COMPANY LIMITED ('ROC')
                             STOCK EXCHANGE RELEASE

                      ROC FARMS INTO THE JACALA PROSPECT,
                           OFFSHORE WESTERN AUSTRALIA

KEY POINT

•   ROC has entered into a Farmin Agreement with BHP Billiton with regard to
    the Jacala-1 exploration well in WA-351-P in the deep water Carnarvon Basin,
    offshore Western Australia. The well is expected to be drilled during
    4Q2005.

ROC advises that it has entered into a Farmin Agreement with BHP Billiton ('the
Agreement') with regard to WA-351-P in the deep water portion of the Carnarvon
Basin, offshore Western Australia (Attachment 1). The Agreement is subject to
normal industry terms and conditions, including the receipt of relevant Joint
Venture and Government approvals.

Under the terms of the Agreement, ROC will earn a 20% participating interest in
WA-351-P in consideration for paying a share of the cost of the Jacala-1
exploration wildcat well, up to an agreed limit equivalent to US$4 million total
net cost to ROC, including a farmin promote to BHP Billiton. If any additional
well costs are incurred they will be shared proportionately. ROC will not be
required to reimburse any pre-drill permit costs.

As defined by 2D seismic, the Jacala Prospect is a large, simple, 4-way dip
closed structure covering more than 300 sq km/70,000 acres with a vertical
closure in excess of 100m/300ft. It is located in approximately 1,100 metres of
water about 200km west of Barrow Island and 100km northwest of the Enfield Oil
and Gas Field (Attachment 1*). The reservoir target is a sandstone sequence
equivalent in age to the Barrow Group which is well established as a productive
reservoir elsewhere in the basin. The potential reservoir is expected to be
encountered at approximate 2,200 metres sub-sea. The well is expected to
commence drilling during 4Q2005.

Subsequent to the farmin, the WA-351-P Joint Venture will consist of BHP
Billiton (Operator with 55%), a subsidiary of Tap Oil Limited (25%) and ROC
(20%).

Commenting on the farmin, ROC's Chief Executive Officer, Dr John Doran stated
that:

'ROC has no illusion about the Jacala Prospect: it is high risk and high reward.
If it contains oil it could have a very big impact on the Company.

The farmin is consistent with the Company's strategy of serving up to
shareholders several 'big hit' drilling opportunities each year. In this sense,
Jacala-1 will take its place alongside other wells that ROC has lined up as part
of a busy exploration drilling programme for the latter part of 2005. Apart from
Jacala-1 this programme also includes key wells in deep water offshore
Equatorial Guinea and Mauritania, shallow water offshore China, onshore UK and
onshore New Zealand.'


* Map to the copy of this release on ROC's website
(http://www.rocoil.com.au/Pages/ASX_Releases/2005_Releases/May-2005.html)


Dr John Doran                            For further information please contact:
Chief Executive Officer                                                 contact:
                                                                Dr John Doran on
                                                            Tel: [phone]
                                                            Fax: [phone]
                                                     Email: [e-mail]
                                                         Or visit ROC's website:
                                                               www.rocoil.com.au

                                                                   Dr Kevin Hird
                                            General Manager Business Development
                                                       Tel:  [phone]
                                                       Fax:  [phone]
                                                     Email:  [e-mail]

                                                                    Nick Lambert
                                            Bell Pottinger Corporate & Financial
                                                       Tel:  [phone]




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